u/Educational_Farm2725

I’m building a large magnetic whiteboard for my kids using two 4’×8’ 20-gauge steel sheets coated with dry-erase paint. The plan is to mount them one above the other to create one large whiteboard.
What’s the best way to mount the steel sheets to the wall? I’d like to keep them as flat as possible, avoid visible fasteners if I can, and make the installation look clean.
Any recommendations or experience with something similar?