Think little picture, I mean really little picture, the tiniest picture, a picture made for ants, then you have reached the size of a pixel. Now that you have gotten that small and focused, now obsess over each pixel in a 5000 x 5000 pixel image. With bloodshot eyes, you just start banging your head against the wall. Then you soon out and realize you've been working in the wrong layer of the image. You have officially now driven yourself crazy.
Zoom out, plan, and check you layers! Do all of these actions before you dive into the tiny world of pixel obsession.