For me it is simple, sometimes I just feel the need to be Simone and sometimes to be my alter ego. I love both personas, and love being in each of them. There are times I want to be male and others I want to be female, and that is where it comes in. In the right persona at the right time just is right!
When I am female I feel totally female, walk and act that way too. If I close my eyes I can feel a female body around me. Then when I am male I revert to being male. Both feel right at the time, and wrong at others.
I am one of those who wishes there was a pill or some device to change gender back and forth when needed, that would be me in the morning!