What's the point of attracting the momentary attention of passing stranger? আপনি don't need other people to justify your existence. If no one is looking at you, আপনি won't disappear. Your not some kind of vampire that needs acknowledgement to survive.
You'd be surprised how many people notice আপনি already--this I know from experience.
However, if আপনি do want আরো attention, and আপনি don't want to do anything too drastic, wear something that's unusual for you, অথবা style your hair a little differently. That will get others asking what's going on.