I have a solid red baseball cap which, combined with a t-shirt of similar color, have sometimes been mistaken for some sort of uniform and therefore had me ignored. So unless your emergency is getting caught in a bull run, this could help...

Generally, I've found the biggest factor in how people treat you is how you treat yourself: you can traverse a college campus covered in dirt and blood without anyone batting an eyelid. Trust me, I know. wink
Whenever you rest, someone, somewhere is training to kick your ass.