Once you and your daughter set up the desk as desired, make clearing off the desk part of the bedtime routine—initially, with on-site monitoring and supervision and eventually with reminders to start and check-ins when she’s finished. You may find it helpful to take a photograph of the space when you first set it up, so your child has a model to compare her work to. The last step in the process might be for your daughter to look at the photo and see how closely her desk matches it.
Peg Dawson and Richard Guare in Smart but Scattered