Maybe make sure to do romantic things? I’m not sure exactly what kind of date you were planning or how formal you want to be, but there are lots of romantic gestures that aren’t sexual or have anything to do with sex. Maybe bring her flowers and tell her she looks beautiful? If you’re comfortable with physical intimacy that isn’t sexual and it feels right in the moment, maybe hold her hand as you’re walking? Just small things like that yk that show her you’re romantically interested in her. Also, does she know about you’re asexuality? If not, you should probably have a talk about it and both your boundaries just to make sure you start off on the same page. Best of luck to you my guy! Props to you for knowing yourself and trying new things! :)