Cowboy to travel, carrying gold with companion (6)
I believe the answer is:
gaucho
'cowboy' is the definition.
(gaucho is a kind of cowboy)
'travel carrying gold with companion' is the wordplay.
'travel' becomes 'go' ('go' can be a synonym of 'travel'**).
'carrying' means one lot of letters goes inside another.
'gold' becomes 'au' (Au is the chemical symbol for gold).
'with' means one lot of letters go next to another.
'companion' becomes 'ch' (I've seen this in other clues).
'au'+'ch'='auch'
'go' enclosing 'auch' is 'GAUCHO'.
'to' is the link.
(Other definitions for gaucho that I've seen before include "Plain-living person" , "Argentinian cattle-herder" , "Cowboy of Argentine's plains" , "Horseman of the S American plains" , "A cough (anag)" .)