How to Tailor a T-Shirt for Beginners

The purpose of this Instructables document is to explain everything a beginner sewer needs to know in order to tailor one of their t-shirts. The document was written specifically for Georgia Tech students who are looking for a cheap way to make their clothes fit better, but should also be helpful to any beginner sewer.

In addition to explaining the actual steps to tailor a t-shirt, this document also goes into some background information on the sewing terms and tools used in this project, particularly in Steps 1, 2, 3, 7, and 10.

- T-shirt

- Sewing machine (more in Step 2)

- Ironing machine and board

- Ruler

- Sewing pins and/or tailor's chalk

- Sewing thread and needle (more in Step 7)

- Seam ripper

- Fabric scissors

This document uses some sewing terminology, which are explained here:

- Finishing a raw edge: When a fabric is cut, a raw edge is created. This raw edge is made of loose strands and will fray, so it must be finished. Finishing is the process of stitching over a raw edge to contain the loose strands and stop the fraying. This can be done in many different ways, such as by using a machine called a serger or by sewing a zig-zag stitch across the edge. Image 1 shows the fraying of a raw edge.

- Right/wrong sides: The right side of the fabric is the side that is shown on the outside of the garment, and the wrong side of a fabric is the other side which is hidden. On a t-shirt, the right side is simply the outside of the t-shirt, and the wrong side is the inside.

- Seam allowance: Seam allowance is the area of a fabric between the line of stitches and the edge of the fabric. Usually, it is specified with a distance, such as 5/8" or 1/4". For example, the instruction to "sew with a seam allowance of 5/8" " means that the seam line should be made 5/8" away from the edge of the fabric. Image 2 shows the seam allowance on a t-shirt.

- Sewing notions: Another word for sewing tools.

- Side seam/shoulder seam/hem: The side seam on a t-shirt is the seam that goes down the sides of the t-shirt, and not every shirt has one. The shoulder seam is the seam that circumferences the armpit and shoulder. The hem is the bottom edge of the t-shirt, that goes around the waist.

- Straight/back stitch: A straight stitch on a sewing machine is a type of stitch where the thread makes a straight line in the fabric. This is the most commonly-used stitch for making seams. A back stitch is a stitch where the fabric is fed backwards through the sewing machine, and is used to secure the start and end of a straight stitch. Image 3 shows a straight stitch on the bottom and a zig-zag stitch on the top.

- Zig-zag stitch: A zig-zag stitch is another type of stitch where the needle moves left and right on every stitch, creating a zig-zagged line in the fabric. This type of stitch is a simple way to finish a raw edge.

If any Georgia Tech students do not own a sewing machine, there are a few sewing machines around campus available for use. The Hive and the Invention Studio both have sewing machines that are free to use.

Because these processes are different for different sewing machines, this document will not explain how to setup or thread a sewing machine, nor how to select the type, width, or length of a stitch. This document will also not explain the parts of a sewing machine, as that will have already been learned while learning how to setup the sewing machine.

If unfamiliar with any of these concepts, ask a Peer Instructor at the Hive or the Invention Studio for help, or look at the sewing machine's user manual, which are often available online.

Before starting to make changes to the t-shirt, it is important to first know what the end goal is. Of course, the great thing about sewing is that one has the freedom to do whatever they want, so feel free to alter the t-shirt however one likes. However, if the goal is a comfortable and universally-flattering fit, here are some general guidelines:

- Torso: Men's t-shirts' torso should have no more than 2-3 inches of excess when pinched on both sides. Depending on preference, women's t-shirts can often be tighter. In general, the t-shirt should loosely "hug" the body. If there is pulling across the chest, it is too tight.

- Sleeves: In general, the sleeve should have no more than an inch of excess when pinched. It should not be restrictively tight, nor loose enough that it tents away from the arm.

- Armpit area: The t-shirt around the armpit should not be so tight that it pinches the shoulder, but should not be loose enough to create "bat wings" whenever one raises their arms.

Moving the shoulder seam or shortening the torso and sleeve length are both alterations that can be made, but that this document does not cover. Also, remember that there are no hard-and-fast rules to fit, except to simply wear whatever makes one happy.

(For a more in-depth explanation of t-shirt fit, Imri Merritt from Rush Order Tees has an excellent blog post on the subject: www.rushordertees.com/blog/how-a-t-shirt-should-fit/ )

To start the tailoring process, it is first necessary to measure how much the t-shirt needs to be taken in. Though not necessary, a friend can be helpful for this step.

First, put on the t-shirt as normally. Then, gently pinch the excess fabric at the sleeves and down the side seam, taking measurements of the amount of excess fabric at each point. In general, four measurements are sufficient: at the sleeve, around the chest, around the waist, and at the hem. Image 1 shows the four measurements taken from the sample t-shirt.

Now, calculate how much fabric needs to be taken in at each point of the t-shirt by taking the difference between the desired and the actual amount of excess fabric. If unsure how tight one wants the t-shirt, aim for a fit that is slightly too large rather than one that is too small (more on that in Step 9).

Most t-shirts have a side-seam, but many do not. Either way, the fabric at the side seam or at where one would be needs to ironed flat before sewing.

Take off the t-shirt and turn it inside-out. If the t-shirt has a side seam, simply flatten the shirt alongside each side seam. If the shirt does not have a side seam, lay it flat according to where one would be. Usually, the seam of the sleeve can be used to determine where the side seam would be.

Iron the t-shirt alongside the side seam, all the way from the arm hole down to the hem.

Images 1 and 2 show a shirt with a side seam before and after ironing. Images 3 and 4 show a shirt without a side seam before and after ironing.

Before sewing the seam, it is helpful to mark a guiding line that will be followed while sewing. Tailor's chalk and sewing pins are both great ways to draw such a line:

- Tailor's chalk: Tailor's chalk is a washable chalk used to draw on fabric. If using tailor's chalk, mark the t-shirt by simply drawing on the fabric, like a pencil on paper.

- Sewing pins: Sewing pins are straight pins used to hold fabric together for sewing. To use them, poke them down then back up through the fabric. If using sewing pins, mark the t-shirt by placing pins where a line would be, thus creating a sort of dotted line. Remember to remove the pins while sewing so as to not sew on top of the pins.

Using the calculations from Step 4 and a ruler, measure out and mark points from both side seams of the t-shirt where the new side seam will be. Images 1 and 2 show the four points marked out with tailor's chalk and sewing pins.

Then, connect the points with either tailor's chalk or sewing pins, creating the guiding line. This is the line that will be followed when sewing the straight stitch in Step 8. Images 3 and 4 show the guiding lines marked out with tailor's chalk and sewing pins.

Before sewing the t-shirt, thread the sewing machine. Choose a polyester thread that matches the same color as the t-shirt, as this will help to hide the seam. Image 1 shows several possible thread colors for the sample t-shirt.

There are many different kinds of sewing machine needles which are designed to be used for different kinds of fabric. The best needle for this project is either an 80/12 universal needle or 80/12 ballpoint/jersey needle:

- The "80/12" simply describes the size of the needle; "90/14" is a larger needle, and "70/10" is a smaller needle. All three sizes will work fine for this project, but "80/12" are the most common.

- A universal needle is the most common type of sewing machine needle, and can be used for most types of fabrics and applications.

- A ballpoint needle, also known as a jersey needle, has a duller point than a universal needle, which helps keep it from puncturing the threads of a knit fabric, such as those in a t-shirt.

If unsure what needle is in one's sewing machine, then one can change out the needle by following their sewing machine's instruction manual. Or, feel free to simply use whatever needle is already one's sewing machine. For a project like this, an "incorrect" needle will rarely make a noticeable difference on the end result. Image 2 shows some universal and ballpoint needles of various sizes.

In this step, a draft seam will be created, which is used to test the draft fit before making the final seam. On the sewing machine, select a straight stitch and set the length to the maximum. A stitch with a longer length is easier to remove in case the draft fit needs to be changed.

To sew the draft straight stitch:

- Place the t-shirt into the sewing machine at the start of one of the guiding lines, about half an inch from the edge. Image 1 shows a t-shirt correctly positioned in the sewing machine.

- Lower the presser foot, and then while holding the excess threads, use the hand wheel to straight stitch once.

- Carefully backstitch off the edge of the fabric, then follow the line all the way up the t-shirt with the straight stitch. Images 2 and 3 shows a straight stitch being made while following tailor's chalk or sewing pins.

- Once one gets to the other end of the t-shirt, straight stitch off the edge, back stitch a few times back onto the fabric, then finish with a couple of straight stitches.

- Cut off the excess threads, then repeat everything for the other side of the t-shirt. Image 4 shows a completed draft stitch.

A few tips while making this straight stitch:

- At the start and end, make sure to line up the edges of the fabric.

- Be careful not to stretch the fabric while sewing. Do not shove or pull the fabric through the sewing machine. Rather, gently guide it with one's hands and let the sewing machine do the work.

- To keep a straight line, try to avoid making constant adjustments, and do not stare at the needle. Rather, let the sewing machine guide the fabric, and follow the line by looking at the front of the presser foot, or wherever one finds most successful.

Now that a new seam has been created, test the fit. Turn the t-shirt right-side out again and put on the shirt. Look in a mirror and move one's body around to evaluate the draft fit.

- If happy with the draft fit, skip to Step 11.

- If the t-shirt is too large, the draft seam does not need to be removed. Rather, simply make a new draft seam where needed, and the old seam will simply either be cut away or will be hidden in the seam allowance.

- If the t-shirt is too tight, then continue to Step 10 to remove the unwanted stitches. Then redo the seam further away from the center of the t-shirt.

If a mistake is made while sewing or if the draft fit is too tight, then a seam ripper will have to be used to remove the unwanted stitches. A seam ripper is made of three parts:

- Blade: The blade is located in between the two prongs or ends. Use this part to actually cut the unwanted stitches.

- Pointed end: One of the prongs is longer and pointed. Use this tip to slide the seam ripper underneath a single stitch, and then carefully cut the stitch without cutting any of the fabric. Image 1 shows the pointed end being used to cut an individual stitch.

- Red ball: The other prong is shorter and has a red ball on its end. Once a few stitches have been cut with the pointed tip, use the red ball to cut a line of stitches quickly. Place the red ball between the two layers of fabric, then slide the seam ripper's blade through the line of stitches. Image 2 shows the red ball being used to slide through a line of stitches.

To remove a draft seam, use the pointed tip to carefully remove both ends of the seam, including the backstitches. Then, use the red ball to quickly cut through the rest of the seam. Finally, pull out and discard the pieces of threads from the fabric. Image 3 shows a stitch after it has been ripped.

Once happy with the t-shirt's fit, one will now strengthen the draft seam with a final straight stitch. This final stitch will have a shorter length, which is stronger and helps keep the t-shirt's seam from coming apart.

Flip the t-shirt inside-out again, and shorten the length of the sewing machine to around 2.5-3.0mm. Sew another straight stitch directly on top of the draft seam, including both backstitches at both ends of the stitch. The same tips from Step 8 apply here.

Image 1 shows the draft seam being followed while sewing the final straight stitch. Image 2 shows the final side seam.

With the seam finished, cut off the excess fabric using fabric scissors, which are extra-sharp scissors specifically designed to easily cut fabric. Be sure to never use fabric scissors on anything other than fabric, as doing so will dull the blades and ruin the scissors. Image 1 shows the excess seam allowance being cut off.

To trim the seam allowance, carefully cut about 1/4-3/8" away from the finished seams, which will create a raw edge. Image 2 shows the raw edge on the sample t-shirt.

Finally, the last step is to finish the newly-created raw edge using a zig-zag stitch. To sew the zig-zag stitch:

- On the sewing machine, select a zig-zag stitch and set the width to the maximum.

- Place the seam allowance into the sewing machine right at the edge of the hem. Line up the raw edge near the middle of the presser foot, and pull out several inches of excess thread. Image 1 shows the sample t-shirt positioned correctly in the sewing machine.

- Lower the presser foot, and while holding onto the excess thread, use the hand wheel until the needle goes down into the fabric.

- Make a zig-zag stitch all the way down the raw edge without backstitching on either ends. Keep the edge of the seam allowance lined up in the middle of the presser foot, so that the needle goes once into the fabric, then once off the fabric. Images 2 and 3 show the needle going down off the fabric then on the fabric.

- Once one gets to the sleeve edge, zig-zag stitch off the edge without backstitching, and then cut off several more inches of excess thread.

- At both ends of the newly-finished edge, tie the excess thread into knots together a few times to secure the ends of the zig-zag stitch. Image 4 shows a completed zig-zag stitch.

Repeat for the other raw edge. Once this has been done, the t-shirt is complete.