Wash the garment
First of all, thoroughly wash the garment that needs to be patched. Dry the cloth for some time to make sure all wrinkles are removed. The cloth should be smooth as the patch will not adhere if it is wet or has wrinkles.
Place the patch on the cloth
Place the cloth flat on the ironing board. Set the garment in a way that the area where the patch needs to be applied comes in the center. You need to place a washcloth on the area before you apply a patch so that direct heat is not applied to it.
Place the iron on the patch and move it
Set the iron on the washcloth. Make sure the iron is properly heated before you apply it to the washcloth. Move the iron in circular motion for a good 2 minutes to apply the patch nicely.
Remove the iron to check the patch
After the required time, remove the iron from the cloth to check whether the patch has been applied correctly. In case the answer is negative, you should stop the process and start again with a new one. In the end, set the garment aside for a few moments.