If the sheet covers a window that has yet to be installed, cover the window with drywall the same way you covered the outlet. Later, rout out the drywall and add drywall screws around the opening as necessary. If the window is already in place, take off the window trim and cut the drywall before you hang it. Lay out the cut by positioning the sheet along the floor and marking where it meets the edge of the windows. Measure from the ceiling to the window top to lay out the top of the cut. Lay out a door cut the same way as a window. Remove the trim, lean the piece against the opening, mark the location of the studs, and draw a line for the top of the door opening. Make cuts for both doors and windows with a drywall saw, then screw the panels in place.