I'll give you one tip I recently learned, and it's a good one. First of all, use paper tape instead of fiberglass mesh. When doing butt joints (no tapered edges), wet your paper tape before laying it in the mud. Make one pass over it to squeeze excess mud from underneath the tape, then smooth it over with a mud filled knife in one clean pass. Don't leave anything behind to sand. The next, and with any luck, the last coat is the only one you want to sand very lightly. Use Durabond 90 for that first coat, and you'll be able to apply the finish coat a couple hours later.
It's worth learning how to apply it well, so it won't need much sanding. Takes a little more effort, but it's worth it. Make the final coat more wet. About the consistency of... moistened toothpaste, I guess.