I do a lot of applique. I use an iron on backing that adheres to the fabric. You pull off the white paper coating and put that side face down where you are going to applique. I use the small little iron to press a piece of it in place to hold it to the fabric, it glues the applique in place so it does not move or pucker the fabric while completeing the applique. Then you continue with your applique. When it is finished I iron the entire piece of applique. The applique material never puckers after being washing and always looks like brand new. I have sweatshirts I have done using this method and washed them dozens of time.
We do not test or endorse any of the tips listed here.
You are cautioned to follow them at your own risk.