Carry out with tact outside. Ran first service (8)
I believe the answer is:
transact
'carry out' is the definition.
(I've seen this before)
'tact outside ran first service' is the wordplay.
'outside' indicates putting letters inside.
'first service' becomes 's' (1st letter of 'service').
'ran'+'s'='rans'
'tact' going around 'rans' is 'TRANSACT'.
'with' acts as a link.
(Other definitions for transact that I've seen before include "Manage" , "Conduct business, negotiate" , "Conduct trade" , "Buy or sell" , "Carry out, like business" .)