For a month? Boy do you have your limits here.
Depending on how you're playing here's how it can go.
Early TL;DR, Look for things members can get that's non-mem later on and work hard as ever with your bonus.
Reason being... there's literally no way to spend your member time wisely,
at least with a month, you won't get very far unless you game AQW a lot.
Anyways, let's assume you play legit and you actually plan on getting a much crap as you can that'll benefit you, beastmaster isn't worth it, leave it alone, i'm serious, take that crap off your list. elemental is recommended by me as a farming/single target class, but isn't meant for powerful bosses, i THINK archfiend is mem only, so again, not a beneficial use of time in the long run, and CA is AC non-mem so that's literally your only thing you should start immediately.
POINT BEING: Use your membership and get things that would benefit you as a non-member, such as getting CA and uhm, other cool crap.
I'm not much help but I got my point across.