When you wash your hands, make sure you are using a mild hand wash or soap so that it doesn't dry your hands.
Gently Exfoliate your hands to remove any dead skin cells present.
Regularly moisturizing makes your hands soft and hydrated
Put on some hand cream after you moisturize them to further remove dry skin.
Get a humidifier and use it to make your hands hydrated in dry winters.
Manicure your hands so that it doesn't collect dirt and germs.
When you're working in wet conditions make sure you wear gloves to protect your hands.