At first you should clean of the coils then outdoor condensers and start it after switched off your device. Filter should be changed after 6 months due to dust particles it keeps away dust to indoor coil , and please don’t touch the refrigerant side of the ac because you are not properly trained.

Dry the Air-conditioner With Disconnect the Unit from its Power Source then Cover the Unit with a Cleaning Bag Now its turn to Detach the Front Panel Wash the Air Filters Clean the dust particles from Filters Clean the Cooling Fins with Antifungal Spray Flush the Drain Lines Turn on the AC to Clean Itself