I would also add that being attractive is not the same thing as passing.
A mistake that many transgender women make is thinking they are the same thing. The logic is that if I look like an attractive woman, then no one will question that I am a woman. But that sets the bar too high, and reaching that goal is very difficult for most people.
You can be very average-looking and still pass. Women come in all shapes, sizes, and levels of attractiveness. Truly attractive people get a lot of attention. They get noticed.
So the question becomes, "Why?" What is the underlying motivation for such a goal?
Everyone wants to be wanted. Everyone wants to be loved. Even ordinary or unattractive people.
Is it because you want men to find you attractive? Men find different things attractive. Some focus on looks, some on intelligence or sense of humor. Some just enjoy being around someone who is fun to be with.
Are you just wanting attention? From anyone? You can do that without looks just by being flamboyant in your style or behavior.
Beauty is in the eye of the beholder. You can't force someone to find you attractive because they decide what they think that means.
I have met quite a few transgender women who focus on looks. They put a lot of effort into their hair, makeup, and clothing style. They draw attention. And they get clocked fairly easily because they stand out.
The ones who pass blend in. They look like every other woman you see on the street. They pass because they look average. They can still be attractive, or not. But most women are attractive, or not.
The question to ask yourself is why you feel that this is what you must do. What does it do to serve your interests? If you are working with a gender therapist, this would be something worth discussing with them. Once you understand the why, then you can focus on the how.