Just have the drums looked at before you have them turned. It can't hurt, but it's not always necessary. You can only turn your drums so many times before they're not turnable anymore so don't do it just to do it.

What I normally do is take the drums off both sides and work on one set of brakes. That way if you get lost putting them back together you have the other one to look at.

If you need some pointers, PM me and I'll do what I can to help you out.