Here are a few tips:
- Create a website and blog
- Create content/articles featuring your work
- Add social media bookmarking buttons to each article which will allow you and your users to share you content. Be aware there is a difference between Facebook "share" and "like". Like does not share your content.
- Add a Facebook Fanbox to your site allowing visitors to join your Facebook page
- Become a contributor on various sites to gain credibility
- Create a Linkedin profile
- Tweet about your photography
Your blog will serve as a portfolio, promotional and marketing tool. There is so much more but hopefully this will give you some direction. This works well for me, especially since I have been building my portfolio for over 3 years with a wide variety of content.