Since my closet is full of sizes 10 to 18 in pants, I had the hardest time going through my closet looking for the correct size. If I needed to find a pair of pants size 14, I had to look through the entire closet as all sizes were mixed together. I have now separated them into sizes and use size tags for me to find the size I need with no hassle.
Out of heavy cardboard, I made a template. 4 1/2 inches high and 2 1/2 inches wide Measure down 1 inch then Measure 1/2 inch on side then cut a 1 1/2 inch hole that will leave a 1/2 inch on other side. Then I made a slit up to the hole, 1 1/4 on both sides.
Before cutting out the hole, I put Contact Paper on the cardboard to make it stronger. I think the pictures will help you if you do not understand my instructions. I also had fun doing this, made for a pleasant rainy afternoon.