I only size up people I'm about to fight just to figure the odds of me winning said fight other than that the person next to me is just another body in my way unless that person is someone I know edit: sounds cold but eh its true I can careless about the person next to me unless they need help then I'll help them out etc so I'm not a dick I just don't really want to spend my time looking at people
So confused what you mean by this but... I just kind of...look. If in my line of vision I see long hair and those black spandex pants, I check out the ass. If I see a rasta hat or a Grateful Dead shirt or someone smoking a cigarette I give a nod.. That's about it.
Thats not a very good way to judge character. Although making eye contact is a sign of respect in the US, it is a sign of disrespect in many other cultures, such as some Asian cultures. Also, some people avoid eye contact because of many internal reasons, ie: shy, anxieties, etc. The best way to judge someones character is meeting with them and the impression they leave on you after them.