1) key spoke, I like the run mine with the spoke head on the flange side closest to you. I don't think it really matters.
btw, I also don't really use the key spoke method either as I wansn't taught that way.
2) just stick with a normal 3 cross for your first one. and... i've really never heard of 2 under and 1 over, guess people don't do it cause its weird.
3) also if you screw up. IMMEDIATELY undo the wrong parts and start again, don't stubbornly forge ahead.
4)take a it slow and easy, and do NOT lace/true wheels if your drunk or not in the mood.
that really helps.