I can only answer in terms of my experience and it doesn’t mean that it’s going to work for anyone else.
For me it happened over a period of time and came with understanding a feminist analysis of gender. This allowed me to unpick the different components of sex, gender expression, gendered behaviours, gender roles and gender identity (ie identification with these three components of gender).
I came to understand that the three gender components are forced on us based on our sex. Because I’m male, society placed an expectation on me in terms of my role, my behaviours and my gender expression. I was expected to look and behave like a man. I came to understand that these expectations are socially constructed and artificial and this gave me a completely different view of the world. I could unlink it from sex. From that point I could accept that I’m biologically male, but my “gender identity” (I.e. The cultural gender expression, cultural expectations of gendered behaviours I identify with) was more aligned with that expected of women.
‘Male’ then became just a biological term unlinked from all of the baggage. It doesn’t make the dysphoria go away, and I still don’t like being called a ‘man’ if I’m honest because to me that word is imbued with so much cultural expectation and represents something I can’t identify with in any way.
I also suspect that M2F and F2M are rather different phenomenon. If you want to PM me I’ll happily continue the conversation in private.
Good luck xxx
(Also try asking @redressalert)