Wallpaper is one of the oldest forms of home decorating. It dates back to the 16th century, and since then it has been one of the most popular alternatives to interior painting. Hanging wallpaper is a breeze until you hit those tough-to-work-around areas like windows and door frames. With the right techniques, you'll have no problem getting around those tricky areas.
Hang the wallpaper as you normally would in flat sheets around the frame of the window, but allow 3 inches of the paper to overlap the window frame.
Make a diagonal cut with your box cutter in the wallpaper at the corners of the window frame.
Fold and crease the wallpaper down where the window frame meets the edge of the wall.
Neatly trim the excess wallpaper along the folded crease with your box cutter.