If you are writing about trans people, use their correct pronouns, even if you are talking about their life pre-transition. The only exception to this is if that trans person gives you specific permission to do otherwise. So, if they are a trans woman, you’ll probably refer to them using she/her/hers. If they are a trans man, probably he/him/his. And if they are non-binary, there are a lot of opinions for pronouns, but often they will go by them/they/their. Whatever pronouns a person asks you to use, just use them. It’s polite and respectful, and “they” can be used as a singular pronoun.
Be sure to recognize that for many people, their trans experience isn’t binary. Transgender is an umbrella term for anyone whose gender doesn’t match the gender they were assigned at birth. For non-binary people, this can mean that they were assigned male at birth but now identify as non-binary. So instead of saying “the opposite gender”, you can just say “a different gender”, since there are more than two options.
If you need to talk about a trans person’s appearance, don’t say that they “look like a man” or “look like a woman”, because that can be insulting and very arbitrary. For example, instead you can say that they “pass as a cis man” or “are often perceived as a woman”. “passing” means that most people are perceiving them a certain way. If a trans man is “passing” as a cis man, it means that most strangers are perceiving him as a man. Likewise, if you say someone is often perceived as a woman, that can speak to their experience in dealing with misogyny without claiming that they look a certain way. “Passing” is generally used when someone is perceived as the gender they are and want to be as, while “often perceived as” is more generally used when someone doesn’t want to pass a certain gender but they have to because of fear of losing their job, or fear of their safety, or because their facial structure is more masculine or more feminine, or something else they can’t control. Likewise, “presenting as” is generally used when someone is explicitly trying to pass as the gender they are and want to be perceived as. So, a trans woman wearing a dress and makeup can often e described as “presenting feminine” or something like that.
Don’t ask trans people about their genitals during transgender dating. What genitals they have, and what surgeries they do or don’t have, that’s all private information. You wouldn’t ask a cis person about their genitals. So don’t ask a trans person. Related to that, asking about other surgeries or hormones or transition-related things is unnecessary. A lot of that is really personal for trans people, and while many might feel uncomfortable when answering that questions, it’s really one that you don’t need to ask. If a trans person brings it up first, go ahead and talk to them about it, but make sure they are okay with it. Obviously, if you are good friends with someone and you know that they are comfortable, just talking about it. But as a stranger or at a ts dating, try to avoid asking trans people invasive and privacy questions about their transition.