HELP. Advice needed! How do I behave??? Will see my ex tonight at mutual friend’s small wedding reception

My ex and I of four years broke up exactly a year ago. I still love him. Our mutual friends are having a small after wedding party tonight at our local dive bar. How do I act? What do I do? I want to be warm and nice but not too much as it can make him uncomfortable and me seem clingy. However, I also don’t want to come across as cold or closed off to a potential opportunity for him to approach me. I want him to notice me and see a relaxed confident happy me. I want to attract him. It’s all dancing on a line difficult not to cross and becoming the stalker ex gf. if possible I want to convey in body language or whatever that I still have feelings while not coming across as desperate.

Little back story: Mistakes were made (not cheating) and he decided the relationship couldn’t survive and he ended it. We always stayed on amicable terms. We still text see each other every blue moon in a awkward “hey how are you and things” way.

I never stopped loving him and I’m sure he knows this. What we broke up over is something I think could have been worked through but he is extremely protective of his feelings (child of a very nasty divorce) and emotions. He’s extremely independent, self sufficient, and almost a bit of a loner. I know he probably is still a bit hung up on me, but he’s very practical and frustratingly disciplined at prohibiting his emotions from driving his actions. For the record, I do not chase him or try to persuade him to come back to me.

PS: he still pays my Spotify subscription every month. Lol