1. Don't do all of your laundry on warm. Americans do this all the time. Sort clothes out and use different temperatures for different loads. 
 
2. Load the washer in proper order:  
• Water first 
• Detergent second 
• Clothes third 
 
3. Don't wash your clothes every time you wear them. Something might not be dirty after wearing it just once or even twice. Americans do this more than anyone in the world, and it wears out our clothing. 
 
4. Buy a front loading washer. They are more expensive, but they save energy and get your clothes much cleaner. They also don't damage your clothes as much.