Nail gun will do for sure a trick with a bit of glue
Here's a good video that explains things pretty well Cheryl! I did shiplap on my bathroom ceiling but I used primed shiplap from Home Depot that overlaps. It looks great and I have had no moisture issues. I thought it was easier than cutting all the plywood boards like shown in the video and priming and painting them. I only had to paint my ceiling once it was up since it was already primed. Arauco is the ship lap brand I used found at Home Depot. It comes in different lengths and is already primed. You can look it up on the Home Depot website. I used a nailgun to attach it to the ceiling joists/studs. I did fill in the nail holes with wood putty and sand before I painted. I want to do my bedroom ceiling the same way--it's on my list!