Put on your safety goggles and gloves.
How to cut siding for gables.
Measure the bottom piece of siding to the proper length which is the length of the wall to the roof line minus 2.
Place a fine tooth blade backward on a circular saw.
Hold one edge of the level against the surface of your roof along the edge above the gable and adjust it until the bubble indicates that it is.
Then i draw a plumb line up to the rake on the high side.
With a long level sometimes an 8 ft er i mark a horizontal line on the wall butting one end against the rake.
The backward motion gives you a cleaner cut through your siding.
How to figure out the siding angle for a gable.
Hang a plumb bob from the other end of the level.
To ensure an accurate reading adjust the plumb.