Take a risk, open gate and walk slowly (6)
I believe the answer is:
gamble
'take a risk' is the definition.
(I've seen this before)
'open gate and walk slowly' is the wordplay.
'open' says to take the initial letters (take the opening letter).
'and' is a charade indicator (letters next to each other).
'walk slowly' becomes 'amble' (I've seen this in another clue).
The first letter of 'gate' is 'g'.
'g'+'amble'='GAMBLE'
(Other definitions for gamble that I've seen before include "back" , "Bet -- Procter's partner" , "punt" , "Run a risk" , "Take a chance, speculate" .)