Exactly what u/ColterR123 said, it works for me! It's disarming, and makes you real / relateable. Everyone has someothing they're super scared others will notice - our thing is just more noticeable. THe worst thing you can do is not address it, cuz a) ppl pick on it, thinking you're just nervour, and b) it'll make you stutter more. That's been the case with me. Once it happens, just look them straight in the eye, laugh or smile, and say something to the effect of "So I'm sure you just noticed, but I have a speech impediment where I stutter a lot". 99% of the time I've done this, people have been supportive of me, which diffuses the situation and so I stutter less. Specifically with this girl, I'd mention it's especially worse when I'm nervous / around pretty girls. ;) Let your personality shine through in that moment. And if she's worth a damn, she'll think it's cute. And remember my friend, always take your time! You're worth it!