Make material that’s woven by demo (6)
I believe the answer is:
embody
'make material' is the definition.
'woven by demo' is the wordplay.
'woven' indicates anagramming the letters.
'by'+'demo'='bydemo'
'bydemo' anagrammed gives 'EMBODY'.
'that's' acts as a link.
(Other definitions for embody that I've seen before include "Express concretely - personify" , "Give form to (idea)" , "Give a concrete form to" , "Include (something) as a constituent part" , "Give a visible form to" .)