Although spaghetti-strap and strapless dresses are popular for prom, these styles are not for everyone. Some girls prefer more modest styles that cover their shoulders due to their religious beliefs or personal preferences. Shopping for modest prom dresses can be challenging, especially when more revealing styles are the trend. Luckily, you can add draped sleeves to a prom dress if you have basic sewing skills.
Fold your fabric in half. Cut the fabric along the fold with dressmaker's shears.
Fold one of the fabric pieces in half lengthwise. Fold the fabric in half again widthwise.
Cut about 12 inches of thread. Measure the thread's length with the flexible measuring tape. The longer the thread, the wider the sleeves will be. Tie one end of the thread to your tailor's chalk.
Hold the end of the thread firmly at the folded corner of the fabric. The folded corner is the one without raw edges. Hold the chalk on the opposite side of the fabric with the thread tautly stretched. Draw a quarter circle with the thread by pushing it from one end of the fabric to the opposite end.
Cut around the quarter circle. Unfold the fabric once and you should see a semicircle. This is one of the sleeves.
Repeat Steps 2, 4 and 5 with the other piece of fabric to create the other sleeve.
Put on your dress or put the dress on a dress form. Drape one of the sleeves over your shoulder to determine how you want the sleeve to look. The straight edge goes on the inside and the curved edge rests on your arm. Drape the sleeve from the left side of your dress's neckline to the center of your dress' back.
You can also drape the sleeve from the center of the dress' neckline to the center of the dress' back. Experiment with draping to find the best location. Repeat the process with the other sleeve to see how the dress looks when finished.
Take the dress off if you are wearing it. Place one of the sleeves on the dress. It should still be folded in a semicircle. Pin the front of the sleeve to the front of your dress on the side closest to the center of your chest. Pin the back of the sleeve to the back of your dress and the other sleeve to the dress in the same manner.
Lift the top layer of fabric on one of the sleeves. Sew the bottom layer of the sleeve to the dress with your needle and thread along the neckline. Work from the side closest to the center of your chest to the armpit. Small, straight stitches work well.
Sew the bottom layer of the back of the sleeve to the back of the dress. Move from the center of the back to the armpit. Sew the other sleeve to the dress in the same manner.
Put the top layer of each sleeve down. Sew one or two small stitches through both layers of one of the sleeves to secure the sleeve to the dress. Sew close to where the sleeve meets your armpit on the front of the dress. Secure the other sleeve in the same manner.
Hem the edges of your sleeves if the raw edges look unfinished. If you want to add more color to your dress, use a contrasting color for the sleeves. Add lace for a more formal style. If you cannot find the right fabric for your dress, consider purchasing a bolero jacket or shrug. You can also wrap a shawl around your shoulders.