First, log in as your user. There are a number of security implications in running X windows as root, especially if you may not yet be familiar with some of the tools available. Not trying to be picky, but I am trying to protect your system and help you get off on the right foot.
Then, try running 'startx'. Depending on how well configured your system is, it should be able to bring it up. If not, you'll need to configure X more for your system.