Getting a formal dress, such as a wedding or prom dress, hemmed can cost anywhere from $10 to $100. If you are on a budget and already have some sewing supplies and basic skills, you can hem the dress yourself. This isn't a solo project, though. You will need a friend with steady hands to help you pull off the perfect hem.
Put the dress on. Wear the undergarments and shoes that you will be wearing with the garment for your special occasion. This will ensure the perfect hem length.
Decide on how short you want the dress and add 1/4 inch to that length. Ask your friend to put pins in the dress to mark the new hem by folding the dress to the length you want, plus 1/4 inch, and pin.
Place a pin in the fabric every 2 inches. Make sure the length is even all the way around the dress by measuring each time a pin is placed. Take the dress off carefully to avoid losing pins. Lay the dress out on a flat surface, such as a bed or the floor.
Iron the fold, and sew a line that is 1/8 inch away from the edge of the fold. Your seam should be done with a very small, close together, running stitch.
Cut off the excess fabric, making sure to cut an even line. Cut as close to the seam as possible without cutting the thread. Take out the pins as you cut and set them aside.
Fold the edge over 1/8 inch so that the raw edge made from cutting the material is inside the fold. Pin the fold.
Sew the fold as close to the edge as possible. Iron the hem for a finished look.