Not sure if this has been posted, and for all of y'all who never run a brake on any bike, feel free to ignore, but:

To adjust toe in:

1. fold a lil piece of cardstock in half - that should be about 1.5mm thick, give or take a few microns
2. wedge that piece in between your rim and the back of the brake pad.
3. loosen up the brake pad holder bolt
4. squeeze the lever good and hard. While maintaining pressure, adjust your pad so that it's square to the rim, and hitting it at the right height.
5. While maintaining death grip, wrap electrical tape around the lever and bar to hold the lever in position.
6. tighten up the brake pad bolt
7. rinse and repeat.

To centre your brake pads (info courteousy of Dave Moulton):
1. place a punch or a big old bolt against the brake spring on the far out side. Tap the bolt with a hammer.
2. Is it centred? If not, do it again until it is.
3. squeeze the lever a few times. If the brake pads don't stay centred, either your brake bolt is too loose or your housing is too long (and is pushing the brake back into wonky position). Fix that.