To install a camper skylight, measure the distance between the ribs on the ceiling of the camper, and fit the new skylight into that space to ensure it will be secured. Install the skylight frame and attach it to the ceiling of the camper with screws. Fit the skylight into the frame, and screw that piece in as well. Place sealant between where the ceiling and skylight meet, then attach the domed top to the roof with screws.
If there is not currently a place to install the skylight, measure and cut an appropriate-sized space in the ceiling and roof of the camper with an airsaw. Be sure to measure this space carefully so it fits neatly with the size and shape of the desired skylight. If an airsaw is not immediately available, then a jigsaw is likely to be long and strong enough to make these cuts.
Most skylights and domes are constructed from solid plastic, which means they require only light screwing. Do not over screw the skylight, or the skylight or dome may crack. To ensure the skylight and dome are properly aligned and tightened, check to see that both lie flat and directly against the ceiling and roof respectively.