Try starting small. Reply more. Little things like that. Everything helps. Remember that we are interested in what you have in your life that you would like to tell us about.
The barrier to entry is way lower in a community this size. You don't have to have the most witty thing to say or the hottest meme to share. Your comments and posts will probably be seen by more people than in the "viral or bust" of a bigger site. It's a totally different kind of usage and definitely makes me feel more engaged