Firstly, I'm sure you're a much more interesting person than you believe. Spend so much time in your own head and you start to get repetitive - but only because you hear it all the time. For someone else, that'll be totally new. If that makes sense?
Anyway, something that works for me when I'm nervous is to make a character. That way, in the situation, I'm acting. Say something weird, or trip over? Doesn't matter. It's not me, it's [character]. Give them a little something, like funky posture, or a even just a nickname.
If that doesn't work, at least you tried! What matters most is you're taking a leap of faith and trying. The more you try, the less terrifying it will get. As my mum always says, "feel the fear and do it anyway."
Fear is normal. It's your response to it that makes the difference. You can either not turn up and things will always stay the same, and you'll never know what might have been - or you can turn up, try, and see what comes of it. Maybe things change. Maybe they don't. You won't know until you try.
Good luck and have fun! I'm sure you'll smash it. After all, you got this far. What's a little more?