I will be trying Marge's vinegar solution, but for wrinkles you want to use Magic Sizing. For added stiffness/body you want starch. I'd dampen it a bit with a spritz of water then a spritz of Magic Sizing then Iron dry.
But also, I wouldn't use it if it weren't treated with a permanent press finish. I just came across a piece of that stuff in my box of donated fabric for charity. It smelled a little old and musty, so I washed and dried it. Couldn't believe the wrinkles, so I used it for rags. In my 30 years of quilting, I remember only once coming across a fabric that didn't have a permanent pres finish. Why wouldn't they treat it??? I hope it was cheaper.