Suggest Remedy For Black/blue Color On Sprained Foot

I believe i sprained my foot, it doesnt hurt much but it was a bit swollen and i had a nice black and blue on the inside of my foot. i am able to walk on it just fine, its just a little tender, i cant tell if my foot is cold because its cold out or just cold for no reason at all. is there anything I can do to help with the black and blue?