Iron-on patches featuring cat designs New Set of 16 ~How to Apply Patches~ 1. Place the patch on the material you want to attach it to, and place a pressing cloth over the patch. Use an iron set to a slightly low temperature (dry) to temporarily fix the patch in place. 2. Once the position is fixed, increase the temperature to medium-high and iron for about 20-30 seconds. ※ Be sure to use a cotton pressing cloth.