Friday would be the latest day to arrive if traveling internationally. The wedding ceremony will start around 11 am on Saturday. There will then be a separate dinner reception (see the schedule). Both ceremony and reception will take place at the Villa Cipressi. Plan to spend the whole day there.
Saturday would be OK if staying nearby, such as Bellagio .
Come a day or 2 earlier to beat the jetlag and not fall asleep at the reception.