It has mostly to do with reading what people post.
For example, when @vhab49_PE and @jean15paul_PE were mafia, Vhab attempted to post a "game relevant" analysis and in doing so, call herself out as a townie. She said, "I'm taking myself off the suspect list because I know I'm a townie." Now, that sounds innocent and might be the right thing to say to deflect, but something bothered me about that statement (or maybe I've been reading too many Lee Child novels).
Vhab could have said, "I'm a townie", or "I'm a regular townie" or "I'm leaving myself off the suspect list because I'm a townie." Or, "I'm not mafia". Any of that would have done the job. But instead, she said, "I KNOW I'm a townie." Almost like, I investigated myself and found out I'm a townie (because I'm NOT a townie and maybe someone SHOULD investigate). It almost sounded like it subconsciously came out of guilt, as if she was aware what she was saying was wrong so she was trying to convince herself (as well as the audience) that she was a townie...."I KNOW I'm a townie." lol just sounded strange so I called her out on it.
Later, after we found out she was mafia and we were all trying to figure out the other mafia, I caught JP writing something verbatim to what Vhab said. It was a small thing, but too much of a thing to be purely coincidence. Either one told the other what to say and repeated it publicly, or they shared something in a PM and without realizing said the exact same thing, almost like they planned to say it but failed to coordinate who should say it, so they both did.
So there is an example of my analysis. I have no special powers this round, just a regular townie. I only voted for Salty this round because he asked. I have no other reason so suspect him.
I have my eye on someone else.