It's happened to just about every woman: You buy a beautiful spring dress and step out into the sunshine only to have a moment of panic when you wonder, "Can you see through this dress?" That moment of panic doesn't have to happen. Half-slips are easy to make and require only a few supplies and a trick of the trade. Making your own slip will also save you money, because store-bought slips can be expensive.
How to Sew a Half-slip
Take measurements for the slip. Measure from your waist to the point where you want the slip to end, and write this number down. Measure around your waist (this should be your natural waist, which is the smallest part of you between your belly button and ribs). Write this measurement down; you'll need to use the original number for two different steps.
Add 2 inches to your length measurement to allow for hemming and the elastic pocket. If you choose to put lace on the bottom of the slip, subtract the width of the lace from the final length measurement. Divide your waist measurement by 2 and then add 6 to 8 inches, depending on the desired fullness of the slip.
Draw your pattern on a piece of poster board, using your final measurements. The waist measurement plus 6 to 8 inches will be the width of your slip panel pattern, and the final length measurement will be the length of your pattern.
Double the slip material and pin the poster board pattern to the material. Be careful not to snag the material with the pins. You can save time by placing the length edge of the pattern on the fold of your material and not cutting that edge. This will give you a slip with one side-seam instead of two.
Remove the pattern from the material and place the right sides together, which means with the side of the material that will be seen facing each other.
Sew the side seam(s) closed from the top to the bottom using a sewing machine. The slip will seem too big but the next steps will make it fit your waist.
Measure 1 inch down from the top of your slip and fold the top of the slip down to meet that mark. Pin the top of the slip all the way around, making a pocket. Sew the pocket as close to the edge as you can, leaving an opening of about 1 inch long to thread the elastic through.
Subtract 2 inches from your original waist measurement and cut the elastic to that measurement.
Secure a small safety pin to each end of the elastic. Use one of the safety pins to secure one end of the elastic to the edge of the opening for the elastic. Using the other safety pin thread the elastic around the slip in the pocket. The head of the safety pin should give you something to grab onto to help you thread the elastic through.
Sew the two ends of the elastic together by laying one on top of each other, after checking to be sure the elastic isn't twisted. While you're sewing, put a few stitches through the elastic pocket from top to bottom on the side seams and in the middle of the front and back to ensure the elastic won't turn. Sew closed the opening you used to insert the elastic.
Hem the bottom of the slip by following the same steps you used to create the elastic pocket. Measure 1 inch down from the top of your slip and fold the top of the slip down to meet that mark. Pin the top of the slip all the way around making a pocket. Sew the pocket as close to the edge as you can, all the way around the bottom of the slip.
Sew the lace onto the bottom of the slip. Turn the slip inside out and pin the top of the lace to the hem all the way around the bottom of the slip with about 1/4 inch overlap. Sew the lace down and then sew the overlap of the lace closed.
Be sure to use a small enough gauge needle for the material you are using and that the tension on your sewing machine is set correctly for the material. This is best determined by trial and error, so sew a couple of practice seams to make sure everything is working the way it should.