You're smart to think about monetizing your website from the very beginning. I always say until you're making money, it's just a hobby.
Without knowing more about your website and what it offers, it's hard to tell you exactly how to monetize it, but some general ideas are:
* charging membership fees
* charging a subscription rate
* taking a freemium approach
* using a service like OpenSky or Commission Junction to sell other people's products and services (as appropriate for your visitors)
These are all good ways to start to think about how you can monetize your site.
Lena West is the CEO and Chief Strategist of xynoMedia Technology, a New York-based firm that helps high-growth companies leverage the power of social media, blogs, podcasts and online communities.