I have a question for veteran Bare Minerals users?

I recently bought the starter kit from Ulta. It has 2 foundations inside; medium & medium beige. I tried them both separately and cannot see a difference. Am I using it wrong? Are they meant as a 1 step 2 step foundations system? Sorry the instructions do not say anything about the foundation. I had more help learning to apply it from the sales rep. The little pamphlet inside is not very helpful; but I do like how it covers & it does not make me break out, so I want to keep it.