1. Consider machine washing them. Cotton is the most commonly used material for ugg slippers. Just like cotton clothes, all slippers made of this material are safe to machine wash. 
- Use warm (not hot) water to make sure you won’t shrink your slippers. Use a fairly gentle wash cycle that won’t warp them.  Use the same washing net as you use for your delicate sweaters, if you want to add them to your usual laundry. 
- Dry them at a fairly low temperature. You can also let them air dry. 
2. Fill a sink with warm, soapy water. You can wash your slippers by hand, if you don’t want to machine wash them.  Put a stopper and fill your sink with warm, soapy water. A small amount of liquid detergent will do. 
- Manufacturers of hand-washing detergents will tell you how much to use.
3. Dip the slippers in the water and wave them around. You should make sure the soapy water submerges them. Use your fingers or a soft cloth to rub the interior lining so that the dirt soaks up the product.
4. Let the product act. The soapy solution will not harm the cotton. Let the slippers soak for a good ten minutes after rubbing them gently.  You will see the soapy water change color as it loosens the grime.
5. Rinse the slippers. After soaking them, empty the sink. Run water of the same temperature as that used for washing and rinse the slippers thoroughly.  Squeeze the slippers when rinsing them, as you would squeeze out excess soap from a sponge or washcloth.
- You can refill the sink with clean water to rinse them out. Let them soak again for ten minutes. You can also rinse them under the stream of the tap for two to three minutes to get all the soap out.
6. Wring out the slippers. You shouldn’t twist them. It can distort them. Instead, squeeze them several times to remove excess water. 
- You can also wring them out in a towel to absorb excess water. 
7. Let them dry. Set the slippers aside to air dry. You can also use the lukewarm heat of a dryer to dry them. 
- A dryer will also fluff up the soft, plush interior of the ugg slippers.