From what I've seen, there are two basic ways of doing them... one of which I won't do because it freaks me out, the other of which isn't really that hard.
Option 1: Get locked into the blunt position, and slightly pop... just enough to get your back wheels under the coping, then you do a brief fakie-manual until you can set your wheels down. I weird out on the idea of doing them like that because it's too damn easy to set your front wheels down, lock up, and get sore ribs and a swellbow.
Option 2: I like to overcompensate and take the hang-up out of the equation. I made this from an old clip (you might need to view trhe image by itself as the forum will probably shrinkk it):
My basic goal is to tap the front wheels down before the back wheels... I imagine a spot under the coping, then after ollie'ing, I aim for it. It helps me to stay over my board, looking straight down the transition. The further over the transition I am, the more confident (perfect word from venuskukko) I feel in setting the front wheels down.