How many naps and for how long should 12 week old baby have?

My baby is 12 weeks old and is fab at sleeping during night goes down at 8 only stirs a couple of time n gets up about 7. But during the day she wont sleep for long at all n by the end of day she is screaming cos is so sleepy want to start a day time sleep routine with her i was just wondering how long n how many naps she should have!