Honestly, just try and avoid aggressively using gendered pronouns as the default. It's not the end of the world if you do, but if you just stick with using they/them and names until you've had a chance to pick up on the social cues, you'll be fine. And if it's in a situation where no one knows anyone else, and where the social cues aren't giving you the answer, then yeah, that's the time to lead with your name and pronouns.

But none of it's a big issue. Trans folk feel it when you get it wrong. We notice, but we also understand that sometimes mistakes happen, especially in a society that has taught everyone to associate pronouns and assumed gender. What's important isn't that you get it right every time, what's important is that you pay attention when you get it wrong, and do your best to get it right from then on.