I'm not sure I've ever seen a post go for 15 days without a response on this forum NASOK. Sorry about that. As to your question, the answer is relatively simple: Experiment. Get some things together ahead of time before you start taking pictures to help alleviate frustration for not getting immediate results.
If I were you, I would make sure I have a tripod or copy stand, some decent lighting at say 2 and 10 o'clock from where the coin will be sitting, get straight on with the coin from say 8 inches, go will full auto, zoom in as far as you can and still get focus, and use the timer function on the camera to take a picture. Take a look at what that looks like, and adjust from there.
Check out this
LINK. Some good info, and also what to expect. 3 megapixels is pretty low by today's standards, but the macro photos in this review are pretty astonishing. This is a very very good site in my opinion for any camera purchase. I don't think they are very biased towards a particular company. If you don't want to read the entire review, I will tell you what I noticed in the specs. Regular focus is 17" to infinity. You have one macro mode, the flower icon on the right side of your 4 way button, and this will be good for 4cm out to 17". It looks like you would want to use this for all coin shots.
Hope this helps, and post some pics. There are lots of folks that can help you out just by looking at examples.