Paper the acrylic instead of the corner
Most people find it very difficult to tape around the corner. Do not you have to ...
You go with the wallpaper to the corner, everything that goes to wallpaper over the corner, you pull carefully with a drawing board away, so that the wallpaper is just at the corner. Once the room has been wallpapered and the wallpaper / glue is dry, acrylic is pulled into the corners. Acrylic you can then simply paint over and so you have no bumps or sloping wallpaper tracks on corners.
