Don't rush it- your first frame need not be a tosser. If you haven't brazed the tubes together spend as much time as you want cleaning up those lugs. It's much easier to do it before they are all stuck together.
If you haven't already, start brazing some scrap tubing together in lap joints. You will want to have some practice before you move straight to the bike stuff if for no other reasons then the time invested.
Good luck!