1. Waiting until the bag or dust cup is full to empty it - It's best to change it when it's no more than three-quarters full - or empty the dust cup after every two to three uses. This will keep your vacuum's suction strong and cleaning performance at its peak.

2. Cleaning with a dirty filter - You're not removing allergens as effectively if your filter is clogged with grime. You don't have to change the filter as often as the bag, but if the filter shows signs of wear, or is excessively dirty or torn, it's time to replace it.