Do you have a LinkedIn profile?
Is your LinkedIn profile filled in with descriptions of your current and past positions?
How many connections do you have?
What do you know about your connections and what do they know about you?
The key to successfully using LinkedIn to help develop your career is to connect with the people in your network on a regular basis. You may want to organize your contacts in different ways based on how you can help them and how they can help you.
For instance, you may want to identify a few people who are in a position you want to move to someday. You can talk with them about how they got there and what they advise that you do. Or, perhaps, you'd like to mentor someone younger than you.
In either case, you can probably more deeply connect with several people in your LinkedIn contacts list in order to give back and receive some help yourself.
Do more than just collect contacts. Foster your connections and develop relationships.