This sly manoeuvring becomes elegant (7)
I believe the answer is:
stylish
'elegant' is the definition.
(elegant can mean stylish or fancy)
'this sly manoeuvring' is the wordplay.
'manoeuvring' is an anagram indicator.
'this'+'sly'='thissly'
'thissly' anagrammed gives 'STYLISH'.
'becomes' acts as a link.
(Other definitions for stylish that I've seen before include "Soigne" , "Smart - attractively competent" , "Imposingly smart" , "Trendy" , "Chic -- fashionable" .)