Now, some teachers get snooty about 'clear desks'. They automatically put the word 'policy' after it and regard it as a bureaucratic intrusion: being treated like a Victorian child whose parents believe that a 'tidy bedroom equals a tidy mind'.
If you're in that category, then please, please just rise above it. Regardless of how cheesy it is, it WORKS. Not for everybody, obviously, but it is one of the most reliable tricks to transform your own attitude. If you still feel that it demeans you in some way, then try it for a while, and - while you're doing it - talk to yourself about the benefits you're looking for. Most people - sensible greedy lazy people - will seek all these benefits at minimum cost:
a) Start a better working relationship with the cleaners. Allow them a glimpse of what they're supposed to clean.
b) Remind yourself of all the things you're currently working on (some of them may be buried underneath other things you're currently working on)
c) Begin (or re-establish) some logic in storing things. Put your desk equipment away in a drawer. File paper in a place you might remember.
d) (Getting more serious now). Remind yourself of what you HAVE done - not how much you have to do. Put the unfinished work away and mentally focus on achievement.
e) (Getting kind of deep now). Place a bookmark in your mental to-do list: you have done X, and you will start to do Y tomorrow. You know exactly what X is (you've just filed it) and you know exactly what Y is (you've just put it away). No need to lose sleep - YOU are in control.
f) Think about tomorrow: you will arrive to a clean, clear desk - a metaphor representing the fresh challenges that beckon with the dawn.
OK, I got a bit flippant there, but I suspect my audience feels likewise - clear desks can't really change your life, can they? Dunno, but it's worth a try, surely??