First of all, did your bike shop help set up the bike to fit you correctly? The first thing to check is the seat height before messing withing moving it forward or back or tilting the seat. However, the seat will have a clamping mechanism underneath that can be loosened, likely with an allen wrench, so the seat can be moved forward or back, or tilted. However, it is easy to just messed up trying these adjustments and it is best if you have help, ideally from the bike shop where you bought the bike. They really should provide at least some help setting up the bike for you. Handlebar position can also effect how you feel on the seat.

Here are a few abbreviated tips from a quick Google search.

http://www.rei.com/expertadvice/articles/bike+fit.html

This article is excellent, all about saddles and their adjustments: http://sheldonbrown.com/saddles.html