The two main elements of a minimalist design are space and light. The intention is to free up space by using only the fundamental components of a bedroom.
As such, you should simply go for the basics with regard to bedroom furniture, say, a platform bed, a dresser, and a simple nightstand. Since these type of beds do not accommodate a box spring, it important that you choose a strong bed frame and a comfy mattress.
Additionally, you should paint your bedroom in bright colors to introduce an atmosphere of spaciousness. You can counterbalance this effect by using bedroom accessories and pieces of furniture that are darkly finished to contrast the white.