Chalkboard paint allows you to create your own usable chalkboard on nearly any smooth surface. Mixing your own chalkboard paint is easy and gives you the ability to create a chalkboard in nearly any color.
Cover the entire chalkboard with chalk. Doing so "cures" the paint and prepares it for regular use
Wipe away the chalk on the chalkboard using a felt eraser. You could use a wet towel or sponge instead of a felt eraser if you want an even cleaner board
Slide the painted glass back into the picture frame. Secure it to the frame using the frame's backboard
The chalkboard is now complete. You can write or draw on it as you would do with any other chalkboard