Trying to learn to continue the conversation after I open (Say I used the classic seddit advice of 'just say 'hi' or whatver)

How best to follow on the conversation with a stranger?

My instincts are to ask about what their plans are for the night, their name, what they do etc, but I read here from time to time that that's 'boring' - So i'm wondering how to posters who say this is boring tend to transition after THEY open some pretty girl in a bar?