depends on how complex the trip is. When we do driving trips we just take off. On our trip to Tasmania we got on the ferry with the car, off at the other end and just drove. Over the two weeks we only had two pre-made hotel bookings, the rest we just took pot luck that there were going to be vacancies. For cruises we fly up at least the day before. International is much more complex, and generally I book everything ahead of time.