Tips for Hanging Prints
A two or three tile map is designed with a half inch or so overlap. In most cases, the overlap is designed so that you should start by placing the tiles on the right first, then match up the next tile to the left.
Some people have stapled or tacked the maps directly to the wall along the edges, then used trim around the outside to frame it in.
Magnets with a whiteboard
Rare Earth are my favorite but many different magnets do the job. Cheap magnets may rust or spread “magnet dust”
I have not had good experiences with double sided tape, poster tape, mounting squares, or other brands of putty. Thumb tacks work, but they make holes of course.