I went donating blood today and saw a cute girl there. I initially didn't have the guts to talk to her when she was waiting in line, but I saw her again later at the food stand. I just said hi and asked how the blood donation went. Strangely, I was not nervous at all, which I usually am. I just felt the urge to say hello, so I did. Maybe it was because I just lost half a liter of blood lol

Anyways, she was quite responsive and we had a good vibe. Then a nurse came and asked us delightedly whether we are a couple. Of course, we both said no. The nurse had to do a checkup on her because apparently the girl had a complication due to the donation. Out of respect, I stepped a couple of meters away, because I didn't want to intrude her personal space during the medical discussion with the nurse. After that, the girl was ready to leave and came and said goodbye to me. Unfortunately, I did not know how to continue the conversation on the spot, and I just wished her a nice evening (facepalm)

I know that this was an easy approach because of the environmental context. Nonetheless, it's a small victory for me because I'm rather shy usually.