What ever resort you are staying at will have a bus to MK (actually to TTC) plenty early. Just make sure you have your PS # with you - when you get to TTC CMs will direct you to the monorail and you go to MK. There all the way to the left there is a special gate with CMs with clipboards who know all the PSs, they will let you in.
have fun we did this in November - it was a blast....