Homeowner tasks
Change the filter. Clear vegetation two feet back from the outdoor unit. Rinse the outdoor coil from the inside out with a gentle hose. Confirm the condensate float switch works (flip it while the system runs — the system should stop).
Pro tasks
Measured tune-up: static pressure, capacitor microfarads, contactor condition, refrigerant charge by superheat/subcooling, blower amps, temperature split, and condensate treatment.