1. Will you transition at work?
2. If so, how do you think they will handle it?
3. If there is a chance you will lose your job, how will you support yourself?
4. Do you have any support (people or group) you can lean on?
5. Have you begun any physical transition, electrolysis, HRT, etc?
6. How passable are you? (Unfortunately, that matters)
7. Does anyone else know at this time? In other words, have you gotten any feedback about how your friends will handle this?
Those are some of the questions I'd be asking myself today if I were considering transition, now that I've learned what transition can be like. This is how I'd do it today:
1. If you have any doubts or fears about going full time, find a reputable therapist, join a TG group, get as much information as you can as to how others who have done this have fared.
2. Get rid of any and all facial hair. This can take years. Facial hair on a woman isn't well received by the general public.
3. If you aren't on HRT and want to be, the sooner the better, especially at your age. So besides a good therapist, you'll need a TG friendly doctor or a local clinic that honors Informed Consent HRT.
4. Find a mentor. If you don't already have a TG friend you get along with and respect, particularly one who is fully transitioned, try to find one. A common sense friend who has been there, done that can be of great help. Just avoid the "you go girl" rah-rah encouragement that comes without fully knowing your situation. It's kind of like, "Dive in! I think the water's deep enough." And then you crack your skull open.
5. Read, read, read. Get as much information as you can but don't put too much stock in the Internet unless it's well supported. Know what you're getting into before you make any steps that are irreversible.
6. Prepare yourself to lose everything. If you can truly say you can survive losing everything to transition, then you are ready. That doesn't mean you will, but you should be prepared. You will need a lot of emotional strength and a lot of support during transition.
You're in California and that's a plus, at least for many parts, but it's still open season on TGs pretty much everywhere in the US and even where there's laws protecting TGs from discrimination, they often aren't enforced. The more you know, the better you will do. It's better to have a "PhD" going into this than getting "on the job training".
I wish you all the best. You will do well if you prepare well.