Using your Bush DD8411PPB Hepa filter set is easy. First, turn off and unplug your vacuum cleaner. Then, locate the filter compartment and carefully remove the old filters. Place the new cartridge filter and flat filter in their respective spots, making sure they fit snugly. Once done, close the compartment. When using, make sure the vacuum is on a flat surface for better suction. As for maintenance, check the filters regularly, about once a month. If they look dirty, you can gently tap them to remove loose dust. For a deeper clean, you can wash the flat filter with mild soap and water, but let it dry completely before putting it back. The cartridge filter should be replaced when it's too dirty to clean effectively. Always follow these steps to keep your vacuum running at its best.