I'm [17/m] Going On A "Date" With An Ex [17/f] In A Few Days, And Have No Idea How I Should Act

Hello! Basically, I recently came back into contact with a girl that I dated for a year about two years ago. Through talking to her again I realized how much I still like her, and I had a brief moment of confidence where I asked her if she might ever consider dating me again. She said she wasn't sure, but she would be willing to go out sometime(Not on a date) and see what happens. Well it seems our plan is to walk around the mall for a while, so I have no idea what to do or how to act.

For some useful background information, the reason we broke up originally was my fault. My mother died because of an addiction to alcohol so when this ex-girlfriend started drinking I got very mad, not wanting to see her hurt. But I know I can't control her, and I'm fine with it now, I'm over it. She's insanely open about everything. We were just talking yesterday for the first time in a year and she was asking and giving away personal information. Which I don't mind because I dated her for a while so I know I can trust her but it just shows how open she is. And I've seen her boyfriends since. I might be funny but the boys she's dated are buff and mean, which I most definetly can't impersonate. Plus she's not even my typical girl. She's about as hippie as it gets. I'm a total hippie too but not to that extent. Peace love happiness to all, and even in our few hour chat yesterday she managed to slip in at least 10 inspirational quotes.

TL;DR: I want to go out with an ex again, and have no clue how to act on our trial date since she's not normally my type and is very open about the boyfriends shes had since, none of which I compare to physically