Working in the attic is hot, and dark. I have a trouble light that I use, but one light bulb is not a lot of help. To help solve both these problems, I installed a window in the gable over the kitchen.
The window is a Model G42 Andersen Gliding Window. $524.06 from Home Depot
Since it was a "new" install in an open wall, I could frame it in the attic to match the size of the window, which is basically 4 feet wide and 1 foot, 11 inches tall.
On the outside, I trimmed it with 1x4 rough cedar to match the rest of the house, and on the inside, insulation and radiant barrier.