I do as much in advance as I possibly can. As soon as we start looking for a new place, I clean the oven, scrub the grout and scrub the walls. It gets the worst of the job out of the way in plenty of time, then all they need is a quick touch up after we move out. I pack away anything we don't use regularly, minimise wardrobes and bookshelves and minimise the kitchen as early as possible.
Its also a good idea to go looking for damage before moving day. Last move we discovered some damage to an inbuilt shelf on moving day (it was one of the last things to be packed up) and just didn't have time to organise repairs before we had to hand the keys back. I tried to negotiate with the agent to send our own person in for a fix, or even do it ourselves but nope - they deducted a ridiculous price for it from our bond. NOT happy.
Best of luck with the move!