How to Add Panels to a Triangle Dress

Select your fabric to match or complement the coloring and patterns in your dress. Be sure to get the same type of fabric as the existing garment; for example, if the dress is 100 percent cotton, choose another 100-percent cotton fabric. Choose thread that blends in with your fabric or that matches the existing garment stitching color.

Lay the dress on a flat, clean surface, with the area to receive the new panel facing up and central for your working convenience. Use a seam ripper to remove the hem stitching from the skirt, stretching between the nearest two seams on either side of the location for the new panel. Determine the central line for your triangle panel and cut directly from the hem to the waistline or desired panel height.

Splay the incision until your fabric is separated to the size of your desired panel. Using this separation as a pattern template, place your new fabric below the triangle opening and trim the new fabric to the appropriate size. Allow for seams by adding an additional inch on each margin. You can always trim this later if it is in excess of what you need.

Turn your garment inside out, aligning it central and flat on the surface as before. Align the tip of the triangle panel to the tip of the splayed opening. Pin the sides of the panel to the sides of the incision, with the "right sides" of the fabric against each other and facing up toward you. Sew from the hem up to the tip of the triangle and back down the other side. Refinish the skirt hem. Trim excess fabric from the new seams and turn right-side out to wear. Use an iron if necessary to press the new seams.