Using this top tube bag is a breeze. First, attach it to your bike's top tube or head tube using the strap. Make sure it fits snugly within the specified tube diameters. Put your phone in the main compartment and enjoy using it through the transparent film. For small items like credit cards, loose change, and keys, use the second compartment. When it comes to maintenance, wipe it clean with a damp cloth regularly. Avoid exposing it to sharp objects to prevent tears. And keep it away from extreme heat or cold to maintain the material's integrity.