Start with the filtration system, beginning at the pool, clean out the pool's skimmer basket by emptying it into a garbage bag or your garden mulch.
Next, open up the pump's hair & lint basket (found under a clear lid in the front end of the pump), and empty it out also. After this is completed, check the filter pressure gauge, there is no need to do this prior to clearing the baskets as it will not reflect the true pressure at the filter. If, after this process the filter pressure reads high, it needs to be cleaned (ie; backwashed, or dismantled and hosed down) depending on the type of filter.
With a clean filter in operation, visually inspect for leaks and corrosion around all visible plumbing and related equipment, if you have a salt pool you should check for scale build-up on your chlorinator electrode and clean it if needed. Once cleaned, check the chlorinator powerpack and test the unit by turning up chlorine output to 100%, if this is not achievable it may indicate a low salt level or a deteriorating electrode.
Ensure the ground around your equipment is clear of leaves and debris to allow adequate cooling for your pump motor, and keep moisture away from motors, while making it easier to spot any leaks. Remove any debris from on top of your gas heater to eliminate any potential fire hazard. Clear nearby drains of debris to prevent possible flooding of your equipment during heavy rain.