How to Sew Sleeves: Two Methods

Sewing sleeves requires an understanding of pattern pieces as well as the ability to sew in a circular shape. A basic sleeve covers the shoulder and lays flat against the arm. Depending on the outfit you create, you can extend the length of the sleeve to fit the garment’s design.

For beginner sewers, mastering the curved seam line is often a challenge; however, with the right tools and tips, you can practice adding sleeves to your clothing. There are two main ways to sew sleeves into a garment: sewing set-in and sewing flat. While sewing sleeves set-in is a simpler method of adding sleeves to a garment, sewing flat uses a more complex sewing technique.

Familiarizing yourself with the sleeve construction vocabulary will help you understand how to use your pattern pieces. Consider the below terms when sewing a sleeve for the first time:

1. 1. Grain line: Used to guide the cut of a fabric piece, the grain line is the thread along the material. These lines run parallel to the edge of the fabric.
2. 2. Notches: The small triangles on your pattern pieces are called notches. These symbols indicate the sleeve cap as well as the front and back of the sleeve. The single notch at the top of the sleeve represents the shoulder seam, while the notches on the side indicate the front and back of the sleeve.
3. 3. Pattern piece: A pattern piece is a thin sheet of paper that outlines the construction of a garment. Use your sleeve pattern pieces as a guide for cutting and sewing your sleeves.
4. 4. Sleeve cap: Also known as the sleeve head, the top portion of the shoulder covering is the sleeve cap. Slightly arched, the sleeve cap bends to shape the natural bend of the upper arm.
5. 5. Sleeve cap ease: For set-in sleeves, use extra fabric around the shoulder to ease the sleeve into the armhole. As a result, the sleeve cap has a larger measurement than the armhole since the excess fabric creates shape around the shoulder. This larger measurement is the sleeve cap ease.

Set-in sleeves are a type of arm covering sewn separately from the garment’s bodice. After sewing the sleeves and the bodice, you attach—or set—the sleeves into the garment. This method works well when working with woven fabrics or sewing sleeves into a dress. Follow the below tutorial for sewing set-in sleeves:

1. 1. Cut the fabric. Use the pattern piece as a guide to cut out the fabric along the grain for your sleeves. There are two notches for sleeve patterns: One notch indicates the front of the sleeve and two notches indicate the back of the sleeve. Carefully cut out the notches, as you will use them to align the sleeve to the armhole.
2. 2. Construct the sleeve. Pin the right sides of the fabric together, lining up the underarms and placing pins along the raw edges of the fabric every few inches. Stitch the sleeves together using a ⅝-inch seam allowance. Then, position the sleeve cap under the sewing machine, and sew three rows of a basting stitch, leaving long thread tails. The first row should be at ¼ inch, the second should be at ½ inch, and the third should be at ¾ inch. The long thread seam and three rows of stitches will make the easing stitches easier to control as you insert the sleeve.
3. 3. Hem the sleeve. The pattern instructions will indicate the type of hemline you should sew for your sleeve. However, you can also adjust your sleeve length and hemline design according to your personal preference. After sewing the sleeve hemline, you can attach the sleeve to the garment.
4. 4. Pin the sleeves to the bodice. Pin the right side of the sleeve fabric to the right side of the bodice fabric, so the sleeves line up with the armholes. Place one pin at the center of the sleeve cap, leaving the sides unpinned.
5. 5. Pull the thread tails. Gently pull the thread tails from the three basting stitches to gather the sleeve fabric. You can now pin the rest of the sleeve cap in place. The notches and underarms should line up with the side seam as you pin the sleeves.
6. 6. Sew the sleeves to the garment. Set your sewing machine to a straight stitch and mark a ½-inch seam allowance. Starting at the underarm seam, sew the sleeves to the garment, removing the pins as you go. Take your time as you glide the fabric under the needle, and gradually turn the fabric to create a curved seam line.

Since this strategy requires assembling the bodice and sleeves together, sewing flat sleeves can prove more challenging than sewing set-in sleeves. However, using the flat method is useful when working with thick materials, such as knit fabrics. Consider the below step-by-step instructions for adding flat sleeves to a garment:

1. 1. Cut the fabric. Use the sewing pattern as a guide, and cut the fabric along the grain to create your sleeve pieces.
2. 2. Sew the shoulder seams. Align the shoulder seams of your bodice, placing the correct sides of the fabric together. Pin the fabric in place, and sew the shoulder seams using a straight stitch with a ½-inch seam allowance. Leave the rest of the bodice unsewn.
3. 3. Line your sleeves and bodice. Lay your bodice and sleeves on a flat surface. Match the right side of the sleeve fabric with the right side of the garment fabric, and start pinning from the top of the shoulder. Using the center of the shoulder as a guide will ensure the armhole aligns evenly with the sleeve.
4. 4. Sew the sleeves to the garment. Set your sewing machine to a straight stitch and mark a ½-inch seam allowance. Starting at the underarm, sew the sleeves to the garment. Take your time as you glide the fabric under the needle, turning the fabric as you go to create a curved seam line.
5. 5. Finish constructing the garment. Flip your garment inside out and line the edges of the bodice. Add pins along the sides of the bodice to hold the garment in place. Use a ½-inch seam allowance to finish sewing the bottom edge sleeve seam and the sides of the bodice.

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