Just introduce yourself..........ask her what kind of music she's listening to while she's walking....If you two can carry a conversation after that, and you don't say something stupid to scare or insult her, then you're off to a good start.
If she seems to be enjoying the convo, and trying to keep it moving right along, then she's somewhat interested in you.........doesn't mean she likes you, but she hasn't made up her mind yet to hate or be afraid of ya.
But if she starts trying to end it abrubtly, like looking at the clock, or around the room trying to find an escape route, and saying things like........Well, J-F, it's been nice chatting with you but I'm late to pick up my.....kids, boyfriend, husband, mother, dog from the vet, you get the picture. Then it would seem she's looking to find the quickest most polite way to get as far away from you as possible.
Just be yourself, this works best, most of the time......unless the person being themself is a jerk, (not saying you are one, but there are plenty of them )then you'll know pretty fast she's not into you.
Good luck to ya
