Using these Gemfan propellers is easy. First, make sure your quadcopter is turned off. Then, carefully attach the propellers to the motor shafts. Ensure they are tightened properly but don't over - tighten as it might damage the propellers or the motor. When flying, these propellers will give your quadcopter a boost in power and speed. Be careful not to fly in areas with strong winds or near obstacles as it can cause the propellers to break. For maintenance, after each flight, check the propellers for any signs of damage like cracks or chips. If you notice any damage, replace the propeller immediately. Keep the propellers clean by gently wiping them with a soft cloth. Store them in a safe place, away from sharp objects that could scratch or break them.