Design of paper or magazine cutting I twice rejected (7)
I believe the answer is:
origami
'design of paper' is the definition.
'or magazine cutting i twice rejected' is the wordplay.
'i twice' means two replacements for 'i'.
'magazine' becomes 'mag' (abbreviation for magazine).
'cutting' is an insertion indicator (some letters cut their way into a word).
'rejected' says the letters should be written backwards.
'i'+'i'='ii'
'mag' going inside 'ii' is 'imagi'.
'imagi' written backwards gives 'igami'.
'or'+'igami'='ORIGAMI'
(Other definitions for origami that I've seen before include "folding stuff?" , "The folding of sheets" , "Artistic paper folding" , "Creation of objects from paper" , "Japanese crane construction?" .)