simple - the thumb for the the three low strings, the index for the G, the middle for the B, and the ring for the high E. however you may switch fingers when you deem necessary. start by trying some etudes by Fernando Carully, he may be fine for a begginer to fingerpicking. also check the lessons and columns sections in here. good luck and wellcome...

EDIT: try to relax as much as you can. fingerpicking is always tricky when you have tension either in the mind or in the hands. and also try to move your fingers as independent of one another as you can and try to make it "beautiful" - I mean the movements - first of all it's quite impressive, and second - you can create a quite nice playing style not only to hear, but to watch.

EDIT EDIT: you may find that you are overusing some fingers, most likely it's the index. try to overcome the feeling that you need to pick mostly with your chosen finger. It may bring you many troubles in the future if you get used to that. and better search the google for "dirk meineke", he has great site for classical sheet music.
Last edited by Daggoth at May 3, 2008,
try learning some songs with it. try at first a song like "dust in the wind" what you first want to learn is the fingering pattern and you assign a finger per string and basicly it is the same patterns but with different chords. so all you have to do is learn the pattern for your right hand and change chords with your left. fingerpicking is a fun skill with enormous opportunities just be patient and you'll get it down
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no of course. in guitar playing there is never something that you should do 100%, there are only easy and difficult ways to do it. and the best pattern to pick whatever you want is to try to use all of you fingers (if needed) and to do it the way that comes naturally to you.

EDIT: you should try you best to find all hand and finger positions that your comfortable with. always the new things, experiment with others, just don't let you playing become stiff and unnatural, don't let it stay in the same place.
Last edited by Daggoth at May 3, 2008,
There are MANY different finger picking patterns. It depends on the type of music you want to play. I'd suggest getting a book on the style that you are interested in or doing a search on that style.

Good luck