How to Cut Patchwork Shapes

Cut fabric on the grain. First, determine the straight grain of fabric. Make a straight edge cut with the rotary cutter. Next, make a cut with the rotary cutter at a right angle. This makes the base. All of the other cuts start from this squared base.

Decide how large your patch needs to be, and then cut a square, rectangle or bar shape. If you use a ¼-inch seam allowance, allow ½ inch extra in your patch size. Cut the remaining 2 sides on the grain.

Make triangles from squares. Cut a square with the grain. Add enough for your seam allowance. Cut the square in 2 diagonally. Be careful not to pull too hard on the stretchy bias.

Switch the triangle around to make a quarter square triangle. This puts the fabric's grain as the long leg of the triangle rather than the bias. These pieces typically make the outside edge and corner pieces of a quilt.

Use a rectangle as a base for a long triangle patch. Cut a rectangular piece with enough extra for the seam allowance. Then cut it in 2 diagonally to form the long triangle. Make mirror images by alternating the corners.

Lay out patchwork diamonds with a bar shape base that's ½ inch wider than your patch pattern suggests. From the end, cut the proper angle. Measure the distance from that cut to the opposite side of the patch. Cut. Continue cutting diamond shapes to the end of the bar shape.