Trim it with a spiral saw after it s in place.
How to hang sheetrock on walls.
Cut paper beading to fit the height of the wall and press it into place with your fingers.
Protect the corners with metal corner bead.
Hang the abutting panel leaving it long and trim it to create a tight well fitted corner.
A lift makes it possible to hang rock solo but it s still nice to have a helper for loading the rock onto the lift.
Do the same on the adjoining wall.
Cut a piece of drywall long so that it hangs over the corner.
Fasten the bead with 1 inch drywall nails hammered every 10 inches through the perforations in each leg so that the legs are tight to the wall and the corner is not distorted in any way.
On the outside corners apply a layer of compound to either side of the corner.