Rearrange text telling how to put up wallpaper? (3,3,5)
I believe the answer is:
cut and paste
'rearrange text' is the definition.
(moving text from one place to another)
I can't explain the rest of the clue.
(Other definitions for cut and paste that I've seen before include "rearrange text" , "Text-processing operation" , "Computer editing method" , "word processing technique" .)