The outdoor condenser is the part of a central air system that lives in the weather, so most of its upkeep is about giving it room to breathe. Look at the unit every season with the power off. Clear leaves, grass, and loose debris from around the cabinet. Keep shrubs, fences, and stored items back from the sides so air can move freely through the coil. The clearance the manufacturer asks for is printed in the installation manual, and that is the number to follow, not a guess.
When the coil needs a rinse, shut the power at the disconnect first. Use a garden hose at a gentle flow, and rinse from the inside of the cabinet outward if the manual says so, so dirt is pushed out rather than packed deeper. Do not use a pressure washer, because bent fins restrict airflow. If the coil is badly matted or oily, that is a job for a qualified service technician, and it is worth asking what the cleaning includes before any work is authorized.
The condensate drain line is the part that gets missed. Water leaves the indoor coil and runs out through a small line, usually to a floor drain or an outside point. Check that the line is clear and that water is leaving it. If the system has a float switch or safety shutoff on the drain pan, learn where it is and what it does. A clogged line can shut the system down, and a short flush with clean water along the line is often enough to keep it running. If water appears at the indoor unit, shut the system off and call for service rather than forcing the line.
Write a short log that lives with the system paperwork. Note what you cleared, what you rinsed, what you flushed, and anything that looked unusual, such as a new smell or a slow drain. Keep it as a list you can scan the next time the unit is due for a look, not as a diary. When you need a planning reference for the system as a whole, the central air conditioner page on this site gives the typical service life and when to plan.