I spilled an entire mug of coffee on my mattress at 6:30 in the morning. Not a splash. Not a drip. The full mug. I had set it on the nightstand, knocked it reaching for my phone, and watched brown liquid soak into white fabric in slow motion.

I did not own a steam cleaner. I did not own an upholstery machine. I had baking soda, a spray bottle, and twenty minutes before I needed to leave for work. That turned out to be enough.

The Baking Soda Foundation

Baking soda is the workhorse of mattress cleaning for three reasons: it absorbs moisture, it neutralizes odors, and it is fine enough to brush out without leaving residue.

1. Blot, do not rub. Press paper towels firmly into the wet spot. Replace with dry towels and repeat until the towel comes up mostly dry.
2. Spray with white vinegar. Mist the stain until damp — not soaking. Vinegar breaks down organic stains like coffee, sweat, and urine.
3. Cover with baking soda. Pour a thick layer over the entire stained area.
4. Wait at least four hours. Overnight is better.
5. Vacuum thoroughly. Use the upholstery attachment.

For Yellow Sweat Stains

Mix equal parts hydrogen peroxide and water with a few drops of dish soap. Spray lightly, let sit 10 minutes, blot, then do the baking soda treatment.

I bought a waterproof mattress protector the day after the coffee incident. It cost thirty dollars and has saved my mattress from two more spills and a dog incident.