In order to be successful using forums to do viral marketing there are some things that are required.  Do Your Homework: Prior to joining any forum, you must do some research.
1.    Join relevant forums that are in some way related to the promotion’s primary sales market. For example, someone involved with a health related product, many types of forums could apply….everything from holistic medicine to stay-at-home moms.
2.    Choose popular forums.  There is no point in wasting your time and energy on forums that few members and few posts. Page raking and the amount of active members are two good ways to check for this.
3.    Choose forums that allow sig tags.  If it’s possible read the rules before joining and pay attention to them. Your time is important, too.  It is better to find out that a forum doesn’t allow posts with sig tags before you go to the time and trouble of joining.

After You Have Joined: OK…you have chosen two or three forums that meet your requirements…now what?
1.    Keep your sig tag short and update it regularly.  The ideal thing is to limit yourself to one link, preferably to your main website.
2.    Never create posts that are nothing more than an advertisement. This all but a universal rule and only displays the marketers lack of experience if he does so.  At best this kind of post will be deleted by the monitors….at worst, it is grounds for being banned.
3.    Work the room.  Be an active member on the forum. Plan to spend at least an hour each day there and take the time to get to know the users. Take the time to introduce yourself with intelligent questions depending upon the forum’s topic.  As a marketer becomes a regular member, they will hopefully develop a good reputation and without saying a word about their promotion, those who are interested in their product will approach them.