(Assuming you're wanting hrt, and also assuming you're already out to your family/living buddies)
The first thing that's necessary is an evaluation by a therapist. The evaluation usually includes three months of therapy in order to figure out your background, and a bunch of questions concerning your social, financial, and mental/emotional readiness for hrt.
If I might ask, is your preferred gender expression non-binary or binary? If its non-binary you might be able to start buying clothes first that are more androgynous.
It's usually best to get laser or electrolysis (laser first, then electrolysis) for your face before you go on hrt, just because its more difficult to kill the hairs if they happen to turn vellus.
This is just what I have in mind for my own plan, so do what you see fits your life best right now.
If you want to pm me I'll watch for messages, perhaps I can share some info...but I don't have much info because I'm also just starting my transition.
-Skye