Set a timer for 15 minutes and work on one section of the place. If you can do more than 15 minutes, great! If you just squeak by on 15 minutes, then at least you did it.

I was in DBT and one member had to assemble furniture for her kids before she got them back. She was really overwhelmed and I told her, "Just do one room and one piece of furniture at a time." She was relieved that she didn't have to do it all at once.