For those who love drills which cut well and not only heating up the metal, I've learned to sharpen them by hand thanks to the article "DRILL POINT GEOMETRY" by Joseph Mazoff.
It's pretty interesting to see the different geometries for the different materials but usually it's still fo steel or iron.http://www.newmantools.com/machines/drillpoint.html
My sharpenings :
The first one is the 4 facet sharpening with the chisel point clearly visible
This is what I do on big ones with 8 facets, I do it starting at the size of 12mm or so (1/2") up to 32mm (1 1/4")
Doing so, you don't need any pilot holes thanks to the 5th and 6th facets and it won't walk with the point.
Everything is explained in the link, it took me hours of training to master this and I do it on a simple bench grinder (with a good and sharp stone).
I've done a complete guide with pictures inspired about this but I've made it for my work, it's not in English but everything is comming from there.
Once mastered, you'll even find that new drills are just cutting poorly and you'll resharpen them out of the box. (I don't talk about quality ones with already multiple facets)
Have a good training.