According to some LinkedIn experts you should join as many groups as possible. That maximum has been capped by LinkedIn at 50. That sounds like a lot and it is. What being part of a group does is give you better accessibility to connect with people, create an awareness of you and an ability to learn what is going on within the group's area of expertise.
Join groups to make connections
Once you have joined a group, see who the members are. Are there people from target companies or who used to work in target companies in this group? Before you invite them to join your network, learn about them. See what their interests are. Read whom they are willing to make contact with. Then, when you are ready to invite them, create a personalized invite explaining why you would like to connect with them.
Join groups to become known
Some groups are more active than others. See what discussions have been posted within the group. Take part and add comments to the discussion that are relevant and intelligent. Commenting on people's discussions can ping them so they see your name as well as your comments. Don't go overboard, but DO participate. Remember, you have to give to get. You can add news articles you stumble across that are relevant to the group. Again, this is creating an awareness of you. The lesson here is about being active in the group.
Join groups to learn about trends
Have you ever wondered how to solve a problem at work or with your job search? Chances are the information you are looking for is out on the web somewhere. Search LinkedIn for answers to your questions. Many groups post feeds from industry publications and blogs. Read these.
The important lesson about joining LinkedIn groups is that you want to be active. Ask questions and play it forward as much as possible.
If you are still feeling overwhelmed by LinkedIn, you can go to the LinkedIn Learning Center to get many of your questions answered.
This is a link to their Job Seekers user's guide
This is a link to their overview of Groups
There are lots of blogs and resources that talk about the "Best Use" of LinkedIn.
If you have a favorite source for learning about LinkedIn, please share it with us in a comment!