The average person generates hundreds of kilos of dirty clothes a year, but few of us wash them correctly. Simple steps for cleaner loads:

• If you use a top-loading washing machine, fill a few inches of water, add detergent and then the clothes. Few of us do it in this order, but it can make a difference to the cleaning.
  
• Wait five minutes to add chlorine bleach. Detergent and bleach fight each other when added together. You may get a poorer performance than if you'd just used detergent.
  
• Don't mix powder and liquid detergents. Powders and liquids are different chemically, and they may inhibit each other if used together.
  
• Use the heater sparingly. Heating consumes 25 times more power than a cold wash, which is quite efficient if you use a good detergent.