Button rollover

How can I create button rollover in Flash using ActionScript 3.0.

I have layer with all link, and a layer with ActionScript code.

I didnt created button symbol but movieclip sybol and then in ActionScript layer I wrote this "link1.buttonMode = true; for every button.

So how can I and what is the best way to create rollover effect?

Thanks…

TweenMax
Examples are on the site.