I think the signs were there for me — some I recognized, but dismissed, others may have been more subtle that I outright missed, but looking back at it, might have been a sign.
In my case I started presenting in private and experimenting in private beginning at 13 — so I did go into it fairly early, but I dismissed it as me being trans. At that point “trans” was not even a thing (we are talking 1980s here) and it was just not on my radar. I felt like I must be the only “boy” on earth looking to try on his sisters things, or have the feeling constantly repeating inside of me — “what does being a girl feel like.”
I think for some, and certainly in my case, I created excuses and lived in denial for a very long time. I am 50 now, and I am only now really considering myself transgender and saying out loud not that I want to feel like a woman but rather “I am a woman.” I dismissed it even while engaging in it as first a “phase” then a “fetish.”
Subtle signs that were missed (perhaps missed on purpose) I wanted to spend time with my sister and her friends more than I think was reasonable when I was really young (5-10 years old). During that time I also found it difficult to spend time with boys. I never felt like I fit in. They were more rough and tumble and I was far more demure. The earliest sign I missed — which was years before I ever began experimenting was when I was spending some time with male friends, and they said “lets play football.” I had zero interest. I just walked home after a bit, and I distinctly remember using the following statement, ” …why don’t I like to play football? Am I a sissy or something… maybe i am…” I know “sissy” is an improper term and apologies to those who take offense. The point is, for a 7 year old that was the only term I had in 1978, and it was the depth of my comprehension. I did not understand it other than the vision in my mind — i think for the first time was a very basic idea that “I am a girl.”
I am sure many other signs were missed — and it is both unfortunate and perhaps what is just and right for me. Clearly I could not cope with what I felt and my mind invented ways for me to cope. Now, things are vastly different. Where does it end up — not sure. But the journey is what it is.