Support Points are gained in the following ways:
5 Points per Profile Message
5 Points per Friend
3 Points per day since Registration
1 Point per Post
1 Point per Topic made
Reputation Points work differently.
You can vote + or - for user posts. A + vote will get the user who made the post 1 Point. A - 1 vote will get take 1 Point from the user that made the post.
You can also press the Thanks button to a post in a topic you made. This will give the user who made the post 3 Points. However you can only do this to one poster for each of your topics.
To avoid the exploiting of this system, you only make 5 votes per day. (The Thanks Button can be used at any time.)
NOTE: You can't vote if you have a reputation less than 0.