Things I have done:
1) Break it into smaller tasks that you can check off a list like the one @PandoraBoxx made. Do at least one task each day.
2) Start by picking up everything of one sort, such as all dirty clothes. Then go on to another category.
3) Set a timer and clean as fast as you can until the timer goes off. I generally set mine for 60 minutes.
4) Play an audiobook that you really like and clean while you listen.
5) Find a friend or a sibling who is willing to help you and then do it as a race or a competition.
6) I also do the “box trick” but I use clean plastic trash bags instead. The one for trash can go straight outside to the bin, and the one with clothes for charity can go straight to the laundry room, and then out to the truck for the next time I pass by a donation site. Things that need to be put on shelves I put away as soon as I touch it, and things that belong elsewhere in the house or garage I simply group together and take them all in a bunch.
7) Invite someone to come over several days in advance that you want to impress, and then do any of 1 through 6.
Just do it!