The answer to 'how to maintain gutter' is to regularly clean and inspect your gutters to ensure they are functioning properly. This involves removing leaves, twigs, and other debris that can accumulate and cause blockages, which can lead to water damage and other issues.
It's generally recommended to clean your gutters at least twice a year, typically in the spring and fall. You can do this yourself using a ladder, gloves, and a gutter scoop or trowel. Be sure to take safety precautions, such as having someone hold the ladder steady or using a safety harness. If you're not comfortable working at heights or don't have the necessary equipment, it's best to hire a professional gutter cleaning service.