It's that simple.
A bit of gorilla glue on a tooth pick will add to it staying put.
A steam iron will work better.
A hyper-hot wash cloth placed against it is best.
Gorilla glue needs moisture to activate.
Use a HOT wringed WASHCLOTH so the paper can regroup.
This is contact paper (sticky glue) not wallpaper (wet based glue). I used my hairdryer and a wallpaper roller to patiently flatten out the wrinkles. This stuff has memory, so when you get it where you want it lock it down by reinstalling the panel and screws. I did not need any glue.