The first thing to know about how to clean a wood cutting board is that it should never go in the dishwasher. The high temperature, prolonged contact with water and harsh soap will split, crack, warp and otherwise ruin the surface. Instead of putting it in the dishwasher, you should use soap and water to clean a cutting board by hand.
When you’re done chopping, scrape any food remnants into the trash.
Next, use hot water from the tap, a dash of mild liquid dish soap and a soft sponge to scrub the surface of the board. Give extra attention to any grooves from knife marks that can trap particles.
Rinse the board well with clean water and promptly wipe excess from the surface using a clean towel.
Prop the board on its edge and allow it to air dry completely before storing.
If board looks "dry". Refresh it by wiping it down with mineral oil to make it look new again. (Recommended every 3-6 months depending on use.)