I used these products.
Have the store shake them. Mine were settled and so hard to mix. Ask the paint department to give them a good shake to mix up the paint.
Before taking the doors down paint the inside seam with the magnetic paint, one coat of this is fine, you do not need it magnetic and do not need to write in there. This is just for the color when the doors are open.
After the doors are painted and dry, put them back up. Now you need to cure the chalkboard. To do this simply coat the entire surface with chalk, the side of a piece of chalk works best, then wipe it off.
To clean it, wipe off chalk a soft rag, or chalkboard eraser. Once and a while I will wipe it down with a damp cloth then wipe it with a damp cloth in a bit of mild detergent. Allow to dry completely before writing on it.
I have found that a cloth diaper (also what I dust with) works best because it does not leave any little fibers behind.
I have my family write down grocery items we need on there and I either add it to my big grocery list or take a quick picture with my phone if I am running to the store for a few things. I have also just added a weekly section. All our appointments are in my phone. (Cozi is a great calendar app.) I write them all on there Sunday night so the whole family can see what's coming up. Sometimes I write quotes or To-Do's on it. I also often have a little artist using it!