Polyester is one of the hardest materials to shrink, according to Made Man. This is an advantage if a polyester shirt fits well, but it presents a challenge in getting an oversized shirt to fit.Continue Reading
Set the washing machine to the hottest possible water temperature setting. Polyester shrinks best at the hottest possible temperature, says Made Man.
Dry the shirt on the dryer's hottest setting. The combination of the hot, wet shirt and the hot, dry air contribute to shrinkage.
Try the shirt on. If it fits, the process is complete. If it is still too large, repeat the washing and drying cycles, and try it on again.