We booked at Klook, but try if you can get it on a lower price at Meitetsu Kanko website.
On the day of your travel, go to Meitetsu Bus Center 4F to get your tour sticker and travel guide documents. The office opens at 7:10am, stay nearby the door because there area a lot of tourists who will be waiting outside. The bus was expected to arrive at 8:10am in Gates 27 and 28. But because the earlier bus departures have problems of waiting for their guests, expect that your own departure time will be affected as well.