H.R.
I put my oldest in a bed at 2 yr 1 mo. She did great! Picking out bedding might be hard for a child that young. Are you doing it now because you have a need for the crib (pregnant?)? Otherwise, I'm not sure why you would do it so early on. I agree about setting up routines, as well as talking about rules for bed. For example, we told our daughter not to get out of bed, but to call for mommy or daddy if she needed anything or when she woke in the morning. We did that because we didn't want her up and wandering around the house by herself. Some people put gates on their kids' doors.
She loved it. It's funny, though, because they look so, so tiny in a big bed. Good luck.