At one point or another, most of us mere mortal makers find ourselves with a collection of mushroom like drill bits. Yes, yes, me too. Buy new ones is what most people do, but from time to time a hero arises, one who fights agains dullness and, ok, ok, back to reality. You can sharpen by hand, well, you still need a grinder so by semi-hand. The problem is that it takes a bit of practice before you can claim the title of average. That is why a jig may be better when starting. And this one is for beginners not only because is relatively easy to use but because it is also inexpensive. Video below, Link for the tool below, below.
And because we should always stride to make our own tools, here is my drill bit angle gauge that I made.