A clear desk begins with choosing what needs to stay within reach. Keep the items you use each day near your usual working position, and give everything else a separate home. A small tray can hold loose notes until you have time to sort them.
At the end of a working session, put tools back, close unused notebooks, and remove empty packaging. Leave a short note describing the next task. This makes the surface ready for a new session without requiring a large cleaning effort.
The arrangement does not need to look like a photograph. A useful workspace reflects the work that happens there. Adjust one part at a time and keep the changes that make ordinary tasks easier.