How do you get endorsements if none of your colleagues are on RP?

I would say continue to talk to them and educate them on the benefits of rallypoint. Once you contribute enough here, someone will endorse you for your contributions on rallypoint alone. I have a handful of endorsements form people I have never met, based solely on what they know of me from here.

SSG Williams:

To echo what SFC Gilley has stated, endorcements are not just those you are currently working with, but can be given and received due to perceptions on this website. You should strive to continue to make intelligent and poignant responses to observations, questions, and discussions in order to bring others to know you and how you think.

I was in the same boat when I first got on RP, I recieved endorsements for various reasons, but the majority rewarded me an endorsement because I was willing to take a stand for what I believed in, provided supporting information when avaliable (via website links), being respectful of while debating my fellow RP'ers, and overall being active within the community.

When you speak from the heart, and have knowledge and support in what you speak about, others will notice. Don't worry about endorsements, let them come to you, and always send a thank you message because that person took the time to recognize something special about you.