Rotary Cutting:
Many times, rather than using templates, patches can be cut from strips of fabric by using a rotary cutter, mat and a see-through acrylic ruler. A large rotary cutter can cut through 6-8 layers of fabric, so multiple patches can be cut at one time. Blades are very sharp, so keep the safety shield on when not in use.
Determine the cut dimensions of a patch. On back of ruler, place masking tape along the measurement lines that correspond to the patch dimensions.
Fold fabric in half, selvedges together; place on the cutting mat. Align the ruler perpendicular to the fold and cut the fabric to make a straightedge.
If you are right-handed, place the cut edge of the fabric on your left. Place the ruler on the fabric, aligning one tape edge with the cut edge of the fabric. Hold the ruler down firmly with your left hand. Cutting away from your body, roll the blade against the edge of the ruler to cut strips. Periodically check to see that cuts are perpendicular to the fold.