Sharpening a saw by hand is a difficult, slow, and risk-prone activity. If you mis-align the teeth, you may end up with a duller saw than when you started. If you apply force in the wrong place, you may break the blade altogether.

Sometimes it's just cheaper and easier to buy another saw blade, or even another saw. In the context of programming, that would be consultation or collaboration with a co-worker, or perhaps hiring someone new...