I've been switching for over 30 years now and I've only found two with whom I could easily and fluidly slide back and forth, usually I will have a sub or two plus one Dom/me with whom to let that My sub side out. With the two I mentioned it was a matter of the dynamic, we could flow back and forth between roles without thought because we both trusted our instincts and our knowledge of the other so the only advice I can offer is to cultivate that in your own relationship through communication and shared pleasure in whatever you do.