The short edges of the fabric should be oriented to your left and right sides. You should have one long fabric edge immediately in front of you with the second long fabric edge pointed away from you.

The right edge and top of fabric should form a point as you fold the fabric at a 45 degree angle.

The top right corner should meet at the 45 degree corner at the lower-left edge, in the middle.

The top right angled edge will be close to, but not on, the lower edge of fabric.

After rotating the fabric, the folded edge should be on your right side.

If you have folded your fabric correctly, this cut sliver should come off in 1 long piece.

As you cut off strips, line the new left edge of fabric with the mark you chose on the ruler. Using the same marking on your ruler ensures your strips of fabric are all the same width.