Measure your belt to see how tall it is. Start on the left side. Draw a line from your 1" top mark, along the mark you made 1" from the side. Repeat with the right side.
For example, my belt was 2", so I marked 2" on the back of my pouch, starting at the 1" mark at the top, along the 1" mark from the side. Wipe away any extra chalk after you have made your marks.
Cut slits where you have marked the back of the pouch. Be sure not to cut through the front of the pouch! After you have made the cuts, you can slide the belt through.