Add friends:
1. Search for a person within your niche or a niche in the search bar.
2. Look through their friends (they are likely to be in your niche).
3. Look at their profile. If they are for example interested in networking, seem to share common interests and you like the look of them;
4. Send them a friends request. Make sure to add a personal message. This is how you begin to build a relationship. If you have a landing page you can even put this at the bottom of the personal message.

NB. You have a 5000 friend cap so be selective... and don't try to add more than 25 freinds in a 24hr window or you will get a slap on the wrist and risk a ban.

Groups are a great area for discussion:
Once you have a list of friends within your niche why not invite them to join a group?
The group should be for a specific subject within the niche.
1. Simply create the group and;
2. invite your friends to join (with 1 click). As soon as friends join your group you have the ability to send emails direct into their facebook inbox. You can email the whole group with 1 click.

Groups are great for discussion, conversations. You can moderate the group.
Tip - make sure to put keywords people will search for in the title of the group.

(From a Chris Farrell webinar a couple of weeks ago)

I hope this tips help you.