X59, X58/X60
Take X59 because it takes less time (although I heard that X58/X60) is rather lovely coastal route.
Anyway, remember that you are entitled to have a student discount, because your bus is crossing the bridge.
However there is no return ticket discount in this case, or so I've been told. So you buy on-way ticket and then again one-way ticket to get back. Sometimes, you have to change the bus in Glenrothes, so then you take bus X24 (important notice, check the schedule for details!)
http://www.stagecoachbus.com/PdfUploads ... ife%20.pdfhttp://www.stagecoachbus.com/PdfUploads ... ife%20.pdfIt is really easy to find your way around Bus Station in Edinburgh.