LinkedIn is an interesting social network. It's a great place to meet and connect with people on a professional level, and also a useful tool for finding jobs that suit your interests and skills.
Like any social media platform, you need to be a little persistent at first and continue posting stuff and using the site even if you aren't seeing lots of activity back. Eventually you will and, from a business point of view, it'll be time far more wisely spent than how long you could spend on Facebook or Twitter for example.
Tips for getting into LinkedIn
1. Don't be afraid to approach randomers.
Yes, LinkedIn is quite strict about only adding people that you know - but you can send a request to connect and simply select the option 'friend' when asked how you know someone.
There are limits to how many of those type of requests you can send, but they can be very effective in networking and building your connections.
2. When adding someone, I think the most important thing to do is be original.
There is a default message that shows up when you send someone a request to connect, but you should always personalize it.
Otherwise you'll just end up looking lazy and possibly spammy.
Instead, write something complimentary like "Was just checking out your profile and you look really interesting" or something like that...
It might not work for everyone, but you'll be surprised.
3. Another thing to make use of is LinkedIn groups.
Not all of them are super active, and some of them will be overrun with nonsense and noise, but there are goldmines among them: Places where you can pick up valuable advice or meet your next client even!