I'm inclined to easily open up to people who seem to be confident in areas of life where I lack confidence without being cocky about it. Also it's often easier for me to open up to people who share a similar experience as me (lgbt, black, child of immigrant, etc...)

I have a hard time opening up to people that I find to be rude, dishonest or lacking empathy.

When it comes to straight up attraction I'm not sure I know honestly... But I often end up being attracted to people who are nice to me without being weird, pushy or annoying. Also I like hot guys.