Ok I'm in powderpuff and we ordered these jerseys and you can only pick medium or XL and of course i picked medium, the only reason I did because I thought they would run big. But anyways I'm now stuck with medium and the shirt doesn't fit good but it fits. there is no way I can give it back. So my only solution is to stretch it but it's 100% polyester so is there anything I can do like take it to a place so they can make it bigger or put it in a washer I need it to stretch out so someone help me out PLS!Ok I'm in powderpuff and we ordered these jerseys and you can only pick medium or XL and of course i picked medium, the only reason I did because I thought they would run big. But anyways I'm now stuck with medium and the shirt doesn't fit good but it fits. there is no way I can give it back. So my only solution is to stretch it but it's 100% polyester so is there anything I can do like take it to a place so they can make it bigger or put it in a washer I need it to stretch out so someone help me out PLS!

You can!

I sa a blog post on this the other day, give me 5 min to check browser history.

I would try to wash it in warm water and try stretching it. Then hang it to dry maybe with a weight or pulling it down and/or out (what ever way you need to stretch it) occasionally. I have only had to stretch cotton so I don't know I this will work.