LinkedIn is more of a business networking tool than strictly a social one. It is structured in such a way that your occupation and education are featured more than hobbies and interests for example. However, it works in much the same way as Facebook in that you can invite people to connect with you and join common interest groups. It also has a feature where you can recommend people so it’s great for asking for testimonials.
For lots of advice and free tips, check out the FREEBIES page at the VA Success Group