Also don't go in immediately posting links to your forum. If it's a specific niche, ask the moderators of the sub before you post. You can posts links on your own profile, but honestly no one really looks at that so you probably won't get much engagement there. Going back to karma, you'll need to have a good amount of karma to post on certain subreddits to begin with. Don't ask for karma, because you won't get it and you'll end up getting downvoted quite often.