Well, I have some things going for me.
First off, I'm big. Not like an unwieldy big, but like I can expect my arms and legs to perform. I'm not a slab of muscle, but I can endure pain and be expected to deliver as well. But I look like the dark alley blokes should leave me alone, and they do.
Second, in most cases I am aware. Have to be. I listen to music and walk roads without a sidewalk at midnight. I have to be aware, and so my hearing is such that I can hear the car coming even with music on. Definitely have a good pair of ears, reasonable eyes too.
Third, just my attitude is to take crap from nobody. Even if you say it perpetuates a stereotype, there can always be a grain of truth to the line. I'm an Irish-Italian. If you gave me a pipe and a green hat, I'd be Notre Dame's mascot!
Fourth...did I mention that I keep plenty of weapons, wear steel toes, and can aim a rifle? No? Well, guess what? Yeah. The steel toes are fun too. You get a man in the crotch as is and it HURTS. Do it with steel and he might lose those two boys for good.
Fifthly, and very importantly, I have a good grasp of Jeet Kune Do. Well enough that I did indeed thrust a 300 pound man into the corner of a room with substantial force. Oh yeah. That totally happened. Good times... I think I'm covered.