In the short term: CPC advertising and affiliate marketing (a simplistic route is Adwords + Clickbank, but in general Clickbank products are terrible, you're better off looking further field).
In the long term: Building a legitimate and unique online presence. Start small, cater to niches and gradually branch out in whatever direction seems to be the most profitable. Dedicate a percentage of your revenue to outsourcing content, marketing and improving your services.
You will need to constantly evolve, monitor your competition and build in order to do extremely well.