This information is provided by the National Centre for Transgender Equality on how to navigate airport security as a trans person.
They also suggest carrying a notification card, which can be discretely given to a TSA officer to inform them of your "health condition, disability, or medical device" so that undue attention is not placed on any prosthetics that are part of your gender presentation. For people who travel frequently, it might be worth printing it up and laminating it to save unwanted conversations. I do offer "carry letters" which are the old-fashioned way of notifying security personnel, but I'm wondering if a small printed card might be a more discrete way to manage things? Thoughts?