jockey cap.
depends on his vocation actually and the type of training he
receives.
To don a Guards beret, you have to pass GCC and inducted into
Guards. But you may pass GCC and not have a Guards vocation, in
which case you wear a Guards Tab but not a Guards baret.
same thing for Commando. only that commando don't have a tab.
A storeman/clerk might have some combat infantry traning before
posted to Commando unit, in which case he can wear a green baret
but most will choose not to.