There's no script for social interactions. Most people do masking subconsciously because there's so many things that neueotypicals look for, e.g. body language, facial expressions, micro movements, and how all of them fit together.

You'd need to be superhuman to emulate all of that consciously.

I'm so sorry you have to actively play a part to do this. Usually I always had like 1 friend I can depend on and nowadays when I wanna join friend groups, I still depend on that one friend and then just hang out for a while, before actually interacting.

Turns out, if you just observe and mirror the bigger things, like laughing at their jokes, or looking engaged when they tell stories or similar, you slowly build up trust and connection.

Just remember, it takes time to join a social circle and there's an immense number of setbacks, that you kind of just have to deal with.