How do i know you to be a mason?

Answer 1

Well, first of all, they wear a spesific ring (at least most of them).

Then, when they sign, they put a small dot (.) next to their signature.

What is more, they have a certain handshake when they meet each other!

Apart from these, however, there are no clues because basically they are not allowed to say in public the "secrets" of their society and so we have no way to learn such details!

(there is a book ,though, by ian gittins that gives such information!)