Because it is hard to know exactly how fast you are running, and hence how well you are doing, I put together a Quake-C modification that you can use to measure your progress. Note that the mod doesn't help you go faster by changing the physics of the game at all - the funny behaviour is already there. All it does is give you some feedback on how you are doing.
Once you've learned what kind of timing and technique gives you the best results, you can dispense with the output you get from the mod and use zigzagging and bunny-hopping whenever you play Quake normally. Or maybe just on those special occasions when you need an extra weapon in your backpack.