You can invite individuals to join your team by navigating to the Members tab on your Team Page, and clicking the "Send Invites" button.
This will take you to a new page where you can send out invitations. You can add team members by email, pulling an address book by one of the featured sites, or import them via CSV file.
Check out this article written by our fundraising coaches here at FlipGive to see how you can 'Write Irresistible Invites'!
What's the difference between sharing and inviting people? This article linked here explains it all. Once you've shared your page, be sure to link your supporters to this article to maximize their shopping efforts.