Go the bakers and buy her a roll or doughnut or something. It would get my attention anyway because all I think about is food.
It's a gesture.
"Hi,_ _ _ _ _ _ ", "Quick question. If I knew a guy, let's say me, that liked a girl, let's say you, hypothetically what's the best question I could ask to get your attention?" (then smile and wait. if you talk first, you lose).
No really true.
I disagree about your post.
Maybe they are hard-to-get.
or they just thinking about themselves that they are not easy-to-get. You know girls are like that. I do appreciates those men doing that that being respectful, being generous, being caring you know. Some times you can't blame them if they act like that. They believe also that some men are good at first encounter then afterwards they will find out what their real colors. Well, that's my own opinion ^_^
Stand near her and shout "HEY!" loudly.
That would get most people's attention. Getting someones attention isn't the hard part. It's knowing what to say after you've got it that's hard.
You retain the attention by having something interesting or engaging to say.