A tip I learned at a photo workshop:
Set up your Canon camera so that moving dials and buttons to the left makes the exposure lower (darker); and moving dials/buttons to the right makes the exposure brighter. That is, moving the shutter speed dial to the left should give you higher speeds; and pressing the left aperture button should give you smaller apertures (smaller holes, bigger numbers).
Why? That way, the button and dial movement will correspond with the movement of the exposure indicator at the bottom of the viewfinder, in which minus is to the left, and plus is to the right. Want your exposure to go darker (leftward)? Move the dial to the left.
Most, or maybe all, of Canon’s cameras are set up to not do it that way, but you can set it up that way using the custom functions. For Nikons, the exposure values are reversed; the plus is to the left, the minus is on the right, so reverse everything above:
