Last January, the skin on my knuckles cracked and bled. Washing my hands hurt. Putting on gloves hurt. I was slathering on hand cream six times a day and nothing was working. My dermatologist sister watched me do it once and said, “You are doing it wrong.”

She was right. The hand cream itself was fine. The way I was using it was the problem.

The mistake most people make

Hand cream goes on dry hands, right? Wrong. Hand cream works best on damp skin. The cream does not add moisture to your skin — it seals in the moisture that is already there. If your skin is bone dry when you apply the cream, there is nothing to seal in.

Think of it like putting a lid on an empty pot. The lid works fine, but there is nothing inside to keep warm.

The right way to moisturize your hands

Wash your hands with warm — not hot — water. Pat them with a towel so they are damp but not dripping. Apply a thick hand cream immediately, while the skin is still damp. The cream traps the water in your skin and your skin absorbs it over the next several minutes.

Use a cream, not a lotion. Lotions are thinner and contain more water and alcohol, which evaporates. Creams have a higher oil content and form a better seal. Look for ingredients like shea butter, lanolin, petrolatum, or dimethicone.

The overnight hack

For severely cracked hands, do this before bed: Apply a thick layer of hand cream to damp hands. Put on a pair of cotton gloves or clean cotton socks over your hands. Sleep with them on.

The gloves keep the cream from rubbing off on your sheets and, more importantly, they create a warm, humid environment that drives the moisture deep into your skin. Eight hours of this is equivalent to about twenty daytime applications.

I did this for three nights in a row last winter and my cracked knuckles healed completely. I now do it once a week during the driest months as prevention.

What to avoid in winter

Hand sanitizer is brutal on cracked skin. The alcohol strips away oils and stings on open cuts. Use soap and water when you can, and follow up with damp-skin cream every time.

Avoid hot water — it feels good on cold hands but strips natural oils faster than warm water. Avoid scrubbing your hands dry with a rough towel. Pat them.

I keep a tube of thick hand cream next to every sink now. Next to the bathroom sink, next to the kitchen sink, in my bag. The best hand cream is the one you actually use.