Use your electronic stud finder to locate and mark each ceiling joist. Use a level and pencil to extend the lines over the whole ceiling showing where they are.
Measure the length of the ceiling along your starting edge, which must run perpendicular to the ceiling joists. Transfer the measurement to a wood ceiling board. Cut the board to size on your miter saw.
Hold the board to the ceiling with the grooved side facing the wall and sitting 3/8 inch out from it. Secure it with your trim nailer, shooting nails through the face of the board and into the joists above it. Shoot in two nails per joist.
Cut the next board to size. Set the grooved side of the new board around the tongue side of the previously hung board. Secure the second board with trim nails shot through the sides, just above the tongue, at each joist.
Repeat for each board, crossing the whole ceiling board by board.
Use your table saw to cut the final board along its length to fit against the far wall, leaving a 3/8-inch gap there. Ceiling trim will cover the gaps.