I can often think of some weird but funny line to get girls attention but afterwards I try to have a normal conversation (where are you from, what are you up to, how's your day going etc) but the interaction gets stale and the girl loses interest. Or I keep trying to be exciting and joke around but they stop responding. How do I smoothly shift from a funny opener to get her attention to a conversation so I can establish rapport and ask her out?

Here's an example of a dud convo: http://imgur.com/a/QY9J37r