How do you take the wrinkles out of plastic that has a picture on it?

I have an Elvis Picture on a piece of plastic that is a wall hanging. They call them add ons.

Answers:
Try a blow drier set on low ...apply heat to back side if possible. Thank-you....thank-you very much!

Other answers:
I concur with M&T. Don't hold it on any spot for long either.

I concur with M&T. Don't hold it on any spot for long either.

Put it outside in the sun. Then say,"Elvis has left the building".