Join up components of eleven Rolexes (5)
I believe the answer is:
enrol
'join up' is the definition.
(I've seen this in another clue)
'components of eleven rolexes' is the wordplay.
'components of' says the answer is hidden in the clue (I've seen 'component of' mean this (I've seen this in other clues)).
'ENROL' is hidden within 'eleven rolexes'.
(Other definitions for enrol that I've seen before include "Record" , "Recruit" , "Sign up (member)" , "Sign on, being a loner" , "Register (as member)" .)