Hang things up without holes in the wallpaper
Before I drill holes in the wall I cut with a craft knife a "V" in the wallpaper. The resulting corner, I then dissolve carefully and fold it up. The hole then comes directly into the bare wall. If you later remove the nail or dowel, simply fold down the "V" again and possibly fix it with a little glue stick again. Spared me a lot of trouble with my landlady, when I could present her a hole-free wallpaper, although I had had some pictures and shelves on the wall.
