How to change an alternator on a 2002 gti Peugeot 206?

The battery light, Abs light and Airbag light have all come on and the battery is being drained rapidly. The engine is loosing power at the low revs and switches off and at idle and only responds well when revved high. I thought it may have been the coil pack but im not sure, the other alternative is that the alternator is not charging. Is there a quick fix or test to check what is wrong with it? Failing that, how do i remove it?