A gore is a triangular fabric insert that adds volume to the hem of a garment. Adding gores to an A-line or straight skirt is a cheaper way to make a flared skirt than the traditional method of cutting it from a circular pattern. When adding a gore, you can choose how much volume you'd like to add to a particular section of the garment; more in the back than the front, or longer gores in the front than the back. The wider the bottom of the triangle of the gore, the more volume will be added to the garment. Make a gore from a contrast fabric for a new and quirky look.
Lay the dress on a table or other flat surface.
Decide how many gores you'd like in the dress. The amount should be an even number, between four and twelve, a multiple of four if you'd like the volume split evenly around the dress.
Decide how long you'd like the gores to be. The length of the gores will be the point at which the dress begins to flare.
Make one chalk dot at the hem of the dress where each gore should be placed. The gores should be equally placed around the hem, with an equal amount of gores in each of the four quadrants of the dress; front left, front right, back left and back right. Avoid placing one at center front and center back.
Make a chalk line the length that you'd like the gore, going from the chalk dot that you drew for placement at the hem, and up.
Cut the dress along the chalk lines, from the hem, upward.
Lay your fabric on the table.
Draw a triangle at the top left of the fabric, 1 inch longer than the chalk lines that you drew. The bottom of the triangle should be at least 5 inches wide, but can be wider for more volume.
Cut out the triangle.
Position the triangle on the fabric and cut out another triangle, using the first as a template to cut the second.
Continue to reposition the first triangle on the fabric and cut the triangles out until you've cut out as many triangles as lines that you've made on the dress.
Place one triangle in one cut slit, matching each side of the slit with one side of the triangle, the point at the top of the slit. The bottom of the triangle will extend 1 inch beyond the hem of the dress. Make sure the right side of the fabric of the dress is matched up with the right side of the fabric of the triangle.
Sew the triangle to the dress, beginning from the point, sewing down one side of the triangle, and then sewing from the point down the other side of the triangle, right sides of the triangle and fabric together. The seam allowance will be on the inside of the dress. Sew 1/4 inch from the fabric edge.
Continue to place the triangles into the slits and sew them to the dress.
Turn back the hem of each triangle 1 inch toward the inside of the dress.
Sew the hem 1/2 inch from the folded edge.