I really think you should check out this excellent, comprehensive article by Josh Turner on LinkedIn, called

7 Simple Ways to Boost Your Social Influence Every Day

Josh, who you can follow on Twitter here, gives 7 ways to expand your influence:

1: Actively Connect With Other Influencers

2: Be Active in Places Where Influencers Hang Out

3: Borrow an Influencer’s Audience

4: Be Generous

5: Be a Student

6: Become Known as a Resource

7: Put it on the Calendar

The article is packed full of interesting tips, you really owe it to yourself to check it out.