After the operations done, you can glue the panel.

If during gluing the wallpaper in the room there was a high temperature, or if they were glued to painted and whitewashed walls, the panel may begin to exfoliate. If this happened, you need to carefully pull the exfoliating edge until the wallpaper is easy to tear off, then it is necessary to remove the remains of the paint from them and clean the wall. Then the wall is lubricated with a thick layer of glue, and after 5-7 minutes-wallpaper. This is necessary to soften the previous layer of glue. After the operations done, you can glue the panel.