[nyef]

Click the little up triangle...

[da5e]

Ah, thanks. So that's the mechanism to upvote. So I guess the karma comes from participation and having comments and/or submissions upvoted?

[frossie]

Yes. Each time someone clicks on your little up triangle, whether a comment or a submission, you get +1 karma.

Users with a lot of karma also see "down" triangles and can downvote comments (though not submissions), so try and stay within the guidelines.