Using this Bosch Readyy'y BCHF220AU outer filter is easy. First, make sure your cordless vacuum is turned off and unplugged. Then, locate the dust container on your vacuum. Open it up and carefully remove the old filter. Take your new filter and place it in the same spot where the old one was. Close the dust container. Now you're ready to use your vacuum again. As for maintenance, it's a good idea to check the filter regularly. If it looks dirty, you can gently tap it to remove large dust particles. For a deeper clean, you can wash it with lukewarm water. Just let it dry completely before putting it back in the vacuum. Remember, don't use any harsh chemicals or brushes on the filter, as this could damage it. Using a clean filter will keep your vacuum working at its best and pick up more dirt and dust.