Hi, I've been doing this exercise for quite a while, but I've always had problems with the flick-off's.

Because I don't have very long fingers, when I do flick-off's, I flick it down towards the string below and just let it kind of "slip off" if you will (ex. Flicking-off A string -> finger goes down towards the D string).
I was watching Justin do it, and it seems like he is flicking it OUT from the finger board. This I could only achieve if I have the tip of my finger digging into the fretboard instead of laying it on the fretboard, which puts my wrist in a very awkward position.
This is a problem because everytime I flick-off, I hit the bottom string and it sometimes sounds out too (ex. Flicking-off A string, while hammering-on D string).

Another question, when I play flick-off's, I tend to bend the strings a bit then flick-off, making the note out of tune before I perform the flick-off. Is this because of the way I'm doing this? Or am I not flicking-off fast enough?

PS: These problems occur on the thicker strings more often than the thinner ones, probably cuz it's hard to grip the thick ones.

How do I fix these problems? I really want to get them right so I don't practice the wrong technique. :S

Yamaha Pacifica 112V
Roland Cube 20X

Very, VERY, helpful site!! Free, too.
It's called a pull-off, and the correct technique is to sort of go down, like you described, but it looks like just taking your finger off when watching it, but some players just take their fingers off if they have enough gain to do so, but it's better to get the pulling down technique right because you get a stronger sound and when playing clean, you can hear the legato.

Upgrading to heavier gauge strings will probably help you because of the added tension when the string is at pitch.