A french seam is a wonderful finish for a party dress as it results in a beautiful clean finish. It's a technique used on many high end garments and is a great option if you don't have an overlocker or serger!
Sew a 7mm (1/4”) seam with the WRONG SIDES of fabric TOGETHER.
Iron your seam open and then iron it to one side.
Don't skip this step! It might seam like a waste of time to iron the seam open and then to one side but this is important for a neat finish.
Cut your excess seam allowance back to 3mm (1/8”).
Iron the right sides together.
Take your time to align the fabric so the seam lies neatly along one edge.
Sew a 7mm (1/4”) seam with the RIGHT SIDES of fabric TOGETHER.
This will “encase” the seam we sewed earlier.
Iron your completed seam to one side to “set” the stitches.