Ummm ... if you don't know that, you should first start off with some basic Photoshop tutorials before attempting to create a tux. 
See the one right at the bottom that's marked "Foreground and Background Color Well"? The one on top is for foreground colour, the one under it is for background color. Click whichever one, and select a colour. 

Image taken from this basic tutorial page, in case you'd like to read it. 
And once again, please resize your signature.
EDIT: What foreground to background? Could you quote the part you are having trouble with?
Message edited by uttaresh on 06-15-2009 at 08:48:15 AM
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