Enthusiastic earl drinks in fine writer's advice on strategy (4,5,5)

I haven't cracked this one yet — but the brilliant team at Times for the Times have:

KEEN (enthusiastic) + E (earl), contains (drinks) NOW (in) and THIN (fine), then MY (writer’s). I happen to be good at guessing multi-word phrases from checkers, which is lucky, since this one was a [insert expletive] to parse.