Any tips for first date with ex?

My ex-girlfriend and I reconnected recently. We message each other again and flirt occasionally. Kind of like the time before we got together. To cut the story short we agreed to try going out again. We're going out a week from now and I'm pretty excited to meet her again, but REALLY nervous too. I don't understand why I feel this way. We've been together before already but I don't know. It still feels like the very first time. Lol. Everything seems a foreign to me again. Anyone got tips about going out on dates with exes?