Put pins around seat covers tailor's edging (8)
I believe the answer is:
straddle
'put pins around' is the definition.
(pins can mean legs)
'seat covers tailor's edging' is the wordplay.
'seat' becomes 'saddle' (saddle is a kind of seat**).
'covers' is an insertion indicator.
'edging' suggests removing the centre (edging means the letters on the edges).
'tailor' with its centre removed is 'tr'.
'saddle' placed around 'tr' is 'STRADDLE'.
(Other definitions for straddle that I've seen before include "Stand across" , "Led darts (anag)" , "Span" , "jumping technique" , "Get over" .)