Use firm pressure at 150degC (300 degF) for 12-15 seconds. Make sure to put a barrier between the patch and your heat press or iron such as a white t-shirt or towel. Make sure your jersey lies flat under the patch as it will show creases if there are any. Do not let a metal surface touch the patch or jersey as it can leave heat marks. Wait for it to cool down and peel the plastic layer off when it is a tepid temperature. The patch adheres correctly with a combination of heat and pressure.