For myself, when asked for my phone number, if it feels okay I’ll do so, as well as ask for theirs in return (this generally weeds out the married guys).
I will then call, if they don’t call me first and tell them out of respect and courtesy I’m transsexual and that they should know this about me before going any further.
The majority of the time this happens, they generally opt to not pursue me any further, as this was not what they were looking for.
Imagine going out with one of them and not having told them in advance. That’s how people get hurt.
To summarize, know who you’re going to date before meeting them, set up a support network and criteria to ensure your safety and always tell the truth.