I was able to procure a round trip pass for you on the Canterlot Express (ticket enclosed with this scroll). Please be sure to catch the 10:15 a.m. train to Canterlot, which you can catch at platform B. I've attached a train schedule, as well (see attached second page), however the 10:15 is definitely the train you want to catch. You should make sure to arrive at least thirty minutes early, to be assured of a place to sit on the train. The Saturday trains tend to get fairly full very quickly. 