You're asking how to do an artificial harmonic?
Well, you've got to pick the string in such a way that the fleshy side of your thumb hits the string at the same time as your pick. You'll probably need to adjust the grip on your pick, sort of choke up on it, and dig in kinda hard with your attack. At least digging in hard helps me do it better. Some people, including Zakk if I remember correctly, do it by letting their index finger's nail hit the string instead of their thumb. I've managed to do them that way, but I think it's more akward.
You've also got to hit the right spot on the string when you pick. If you adjust where you strike the string the pitch of the harmonic will change. There are several spots that will throw a good one out there for any given fretted note, but certain spots work much better than others. It's just a technique and a feel that you develop over time.
As far as the vibrato thing, you've just got to wiggle the shit out of it. A really wide, fast vibrato makes them sound better, and the technique is no different for an artificial harmonic than it is for any other note you play.