Attacked by stray dog in East Downtown today

I managed to slowly get to a fire station and get help. A stray dog (big dog, not some toy dog) started playing with me. I humored him a bit, but he quickly started breaking my skin and began pulling at my clothes (he tore my shirt) barking and biting down harder. I had to come back to the fire fighters again; but even as I was about to get home the dog again followed me. I shouldn't have ran but I ran home and luckily he didn't attack me again.

The dog ended up following me home! He's home now, I'm thinking he will go after me again if I run that route. What can I do to prepare for stray dogs? I don't want to hurt them, but I am upset that he broke my skin all over my arm.