You can either find a chalkboard fit to size, or, there's chalkboard paint available at Home Depot, Lowe's, and any store that carries Benjamin Moore Paint for like under $15.
Here are some helpful hints I found at Benjamin Moore's website:
Step #1: Prepare the Surface
Once you've selected the space for your chalkboard, clean the surface completely and repair any protruding nails or other imperfections. Some surfaces may require a primer or additional preparation:
- If an all-purpose primer is needed, we recommend using Fresh Start® High-Hiding All Purpose Primer (046).
- When applying chalkboard paint over plastic, we recommend priming with Insl-x® STIX® Bonding Primer (SXA 110) for best results.
- Metal surfaces should be cleaned with Super Spec HP® Oil & Grease Emulsifier (P83) before applying chalkboard paint.
- Shiny metal surfaces should be lightly sanded before the chalkboard paint is applied.
Use painter's tape to mark off a space for your chalkboard.
Step #3: Apply the Chalkboard Paint
Using a brush or roller, apply the chalkboard paint within the taped-off area. For best results, use a Benjamin Moore custom-blended nylon/polyester brush or short-nap roller.
Step #4: Ensure Lasting Durability
For best results, allow the painted area to cure for 3 days before using it as a chalkboard. Then, prior to initial use, rub the entire surface with a piece of white chalk.
- For erasing, we recommend using a clean, damp cloth or paper towel. We do not recommend using a chalkboard eraser.
- Because of the additives used in some varieties of chalk, which can leave a residue when erased, we recommend using light-colored chalk designed for use on chalkboards.
- Use decorative molding or a colorful painted border to give your chalkboard area an extra personal touch.
- Attach a ledge at the bottom of the painted space to hold your chalk.
- In children's rooms, be sure to make your chalkboard low and large enough so that younger children can reach it and have ample space to write or draw.
- In your office or study, paint a chalkboard calendar with squares for dates. Then update your schedule whenever you like.
- Try a chalkboard in the kitchen for shopping lists, phone messages, and easy recipe reference.
- Think beyond your walls—use chalkboard paint on a child's table, flower pots, or colorful storage boxes.