How to travel at light speed (for fictional story)?

Dear Yahoo! Answerers, I am writing a short story about a boy who travels at light speed, but after some searching, I'm not sure how to make this happen. I understand that it is HUMANLY impossible to travel at light speed, and that theoretically we can come close, but for the sake of my FICTIONAL story, I need to know how to achieve this in the most plausible/logical fashion. Thanks!