Every item in your field of vision costs you energy. Brain scans show that the automatic effort of filtering out irrelevant objects takes power, and the more items you look at, the worse your focus becomes.
You need to see fewer objects. You don’t have to throw anything out (though that is probably good, too). Simply take a number of items that have some relation to each other and put them in a box. 12 USB cables and 7 memory sticks become one object when they go into a box.
Throwing random objects into a box doesn’t trick your brain, however. Looking at a box you know contains random junk actually costs more energy, because now your brain is also thinking about the task of getting the stuff out of the box and sorting it.
Get out a box and remove some clutter from your field of vision. You’ll find that your energy increases. You just might even get around to that task you have been putting off for weeks.