I was 17, about a month into dating my first girlfriend. A mutual friend helped us get together, since my gf liked me but was too shy to say anything, and I was too blind to see it.
Anyway, this mutual friend kept pestering me with texts about when I would kiss my gf, and I kept saying I would get to it. Eventually our friend told me that my gf was the one telling her to keep texting me about it, and when I found that out I promised myself I would kiss her ASAP.
The next time I went over to her house, I was committed to giving her the kiss she so badly wanted. But since this was my first relationship and my first kiss, I was too nervous to make the move. We just sat on her couch and instead of playing video games or watching a movie like we usually did, we just sat there. Waiting. I was holding her hand which felt tingly and numb and my heart was practically beating out of my chest, but I still couldn't bring myself to do it. This went on for around four hours, if I remember correctly, just both of us sitting there in silence waiting for it to happen.
Eventually, it was time for me to leave, and I still hadn't kissed her. I got up, and fully knowing my intentions for that day, she asked if I wanted her to walk me to the car. I said yes. We get to the car and my mind is racing. "It is now or never. I have to do this." I gently grab her by the shoulder and spin her around to face me, and say for the first time, "I love you so much," and go for the kiss. And it was a wonderful kiss. Then right after we were done, she kissed me back! It was spectacular.
She later told me that she thought the way I acted that day was cute, and we can look back on it and laugh at how awkward that whole thing was. She said the way I kissed at first was a little weird but she could tell I would get better at it. And according to her, I did. Two years later and still very happily together. :)
TL;DR Found out she wanted a kiss, was too nervous and just sat there at her house for hours, finally kissed her when she offered to walk me to the car.