I see a lot of people riding plenty of miles on bikes that aren't nearly as nice as what you bought. So just learn a bit about proper maintence, get a few bike specific tools, and ride. Park Tool website has good maintenace info for one -- but there are plenty of others. Bike maintenance isn't rocket science.

Upgrade the seat if it's not comfy. Besides that, just ride it as it is...if you take care of it you'll get lots of miles out of it