Depending on your type of air conditioner, there are multiple ways to clean it. We’ve created a handy guide for those with split systems here: https://www.youtube.com/watch?v=U1TPiB7TQQg.
Generally speaking, you must make sure the air ways and filters are clear of any dirt or debris on a monthly basis, depending on how often you use your air conditioner.
Every air conditioner should have filters installed and these filters need to be washed to maintain optimum performance. Depending on usage the recommended time frame that is recommended between cleaning your filters will vary. If you use your air conditioner daily, your filter should be cleaned at least once a month, for those that use it less often, every three months should be sufficient. Please note that the cleaner the filter, the better the performance.