Have you ever bought a chalkboard, get it home and it sucks? I have, I have even thrown out a couple because I did not know you were suppose to prime your chalkboard.
1) cover the entire chalkboard surface with chalk, use the side and in all directions… left to right, top to bottom, criss cross, just make sure there is a hefty layer of chalk.
2) wipe with a damp cloth.
3) wipe dry
and you are done….
I made these with inexpensive plastic trays from target & lined them with chalkboard contact paper. I am going to use them to take photographs on my kids first day of kindergarten.