Don’t know how to start it back up again

So I’m talking to this friend and it’s going good, except the conversation ended. Now, I don’t know how to start the conversation again. I know I could just say hey, but I feel like that’s a plain and typical response, and need something more personal. I have a bad habit of having a good first convo when I meet someone, and then after we’ve discussed each other’s interests, I don’t know what to say anymore, so I wait for them to start the conversation. Help