Gear:

 1. Battery check (this is done the night before to give time to charge)
 2. Lens check. Since I'm mobile with my gear, I give a little thought to what lenses I should pack with me. 
 1. Flash check. Will I need a fill flash?
 1. Bag check. Will I want my shoulder bag, or my camera backpack?
 1. Memory card check. Do I have enough memory cards?
 1. RS Strap. Is my strap secure. Are there any tears in it?
 1. Lens Hood: Do I need my lens hoods?
 1. Tripod/Gorilla Pod: Do I need my pods?
 
Camera Settings:

 1. ISO
 2. Shooting Mode

For almost all the camera settings, I do these on the fly, depending on the situation. I generally stick to AV, but flip to Manual when necessary. I also have all three custom settings, to quickly switch to less frequently used configurations.

During the actual picture shot itself, I compose, focus lock, (recompose if necessary), take one last look around the view finder, exhale and pull the trigger. I quickly glance at the histogram, and go from there.

After making enough mistakes, this has become completely natural, so I don't need to write anything down.