I am missing something....please explain. I am starting my own website for diabetes awareness. I would like to offer some of the diabetes awareness products that are already available on the cafepress site. I have signed up on Commission Junction and as a CafePress Affiliate. I have also signed up for a CafePress shop. What do I need to do now to be able to put diabetes t-shirts on my website?

You cannot promote products as an affiliate using a cafepress.com domain. In order to promote other people's designs, you need to have your own domain or a blog where you would link to the designs you're promoting.

As for how to link to those products, there's a great tutorial at Tutor Tanith