If you have a straight run gable roof measure from shingle to shingle and then add.
Connecting gutter sections.
Connect the overlapping areas along the sides of the gutters with pop rivets or sheet metal screws.
If you have a straight run gable roof measure from shingle to shingle and then add 1 2 inch to each side.
How to connect two sections of gutters if you are going to put gutters around your house and you have some long sections you are going to have to piece two.
Hang the gutter sections as close you can when.
Spread gutter sealant on the overlapping areas.
How to connect two sections of gutters.
Make sure that the top edge of each overlapping piece is pointed in the direction of the water flow.
Now you can install the gutters.
On the ground assemble the gutter pieces and overlap the sections by 3 to 4 inches.
The first gutter piece and maybe the second and even a third piece will likely be full 10 ft.