Perhaps pretty as a picture on the wall? (8)
I believe the answer is:
tapestry
'a picture on the wall?' is the definition.
I can't tell whether this definition defines the answer.
'perhaps pretty as' is the wordplay.
'perhaps' indicates an anagram.
'pretty'+'as'='prettyas'
'prettyas' anagrammed gives 'TAPESTRY'.
Can you help me to learn more?
(Other definitions for tapestry that I've seen before include "Woven wall-hanging" , "Piece of strong material with picture or design woven into it" , "Embroidered picture" , "Embroidered wall hanging" , "Party set (anag)" .)