As a new user with 500+ followers (Still low, i know), i can say the most valuable thing you can do (Besides posting the ABSOLUTELY VERY BEST CONTENT you can produce) is:

Comment. A lot. and WELL.

I try to comment at least between two or three hours every day. Docens of comments. Meaningful comments. Not "that's so kewl!" comments, but respectful, valuable comment that shows you care. It is incredible how simple this is, and how well this works.

This is a community, so, heck, do some community!

This is my best advice, for newcomers.