You can make the cupcakes ahead and freeze them for a few days. I usually wrap them gently in foil (better if done individually or they may stick) and then put them in a Ziploc bag. Make sure they are completely cold before wrapping them. On the day you want to serve them, unwrap them and let them come to room temperature. If you are decorating them with whipped cream, do so at the last moment or the cream may get spoilt or it may melt.