You get points for posting comments or blog posts. However, please don't post only to get points. It's supposed to be an aggregate measure of contributions to the site over time.

At the moment the feature is in "beta testing" I'd say.

Badges are assigned automatically at certain point thresholds.

I'm pretty new to the whole point system too halo kid, but I'm pretty sure that you get 1 point for submitting a comment and 5 points for creating a blog. You also lose a point if you delete anything. Still not sure how the badge system works though, sorry. Anyways, hope I helped.