There are two ways to add someone to your project tribe.
First, go to your project page and click on "Tribe" at the top.
1.If it is someone you know who is not on ShareYourself, go click the
blue "invite a tribe member" on your project page. Once they receive the
invite, they must sign up, follow your project, and then they can
request to join your tribe or you can add them yourself through tribe
2. If it is an existing member on ShareYourself, you can follow them and
then add them to your tribe, by clicking the blue button "add tribe
Please let me know if this works out for you!