Pennsylvania finally got around to instituting REAL ID a few months ago after several delays and I applied immediately. My usual traveling companion though keeps procrastinating. I told her if she doesn't have one by the time we go on our annual Florida trip in January, I'm going myself and leaving her home.
I don't know how it's done in other states, but in PA, I applied online first, then went to the DMV with my current state ID, birth certificate, proof of address (bank statement) and whatever else was required. Was approved immediately. My card was supposed to take 2 weeks to arrive, but it was in the mail by the end of the same week I applied. No fuss. No muss.