Answer:
If it's really small - your best option is to cut a pinkie mouse into pieces and offer it that way. Sounds gross I know - but feed once every three or four days. After two or three sheds, the snake will be big enough to take whole mouse pinkies.
It will eventually be capable of taking large mice or small mice. I have adult corn snakes (in my collection of roughly 400 reptiles) that will eat two young rats in one meal (the rats have bodies around 4-5 long !)