Commercial applicants are required to log ground or flight training in 11 areas. One of them involves post-flight.
(b) Areas of operation.
(1) For an airplane category rating with a single-engine class rating:
(xi) Postflight procedures.
This is another area that you have been doing since your first flight and Chapter 2 of the Airplane Flying Handbook tells you exactly what is required by this part. So all you have to do is go over it with your CFI and log the ground time.
If you have been doing touch-and-goes you may have gotten into bad habits with flaps, trim, and cowl. The preferred procedure is to wait until you are clear of the runway before you mess with anything. This is especially important with tailwheel planes.
Clear of Runway and Stopped
Because of different configurations and equipment in various airplanes, the after-landing checklist within the AFM/POH must be used. Some of the items may include:
• Power—set to the AFM/POH values such as throttle 1,000 rpm, propeller full forward, mixture leaned.
• Fuel—may require switching tanks and fuel pumps switched off.
• Flaps—set to the retracted position.
• Cowl flaps—may be opened or closed depending on temperature conditions.
• Trim—reset to neutral or takeoff position.
• Lights—may be switched off if not needed, such as strobe lights.
• Avionics—may be switched off or to standby, such as the transponder and frequencies changed to contact ground control or Common Traffic Advisory Frequency (CTAF), as required.
I use BC-FLAGS: Boost Pump Off, Cowl Flaps Open, Flaps Up, Lean Aggressively, Contact Ground, and get some Air into the cockpit.
From the Airplane Flying Handbook:
A flight is not complete until the engine is shut down and the airplane is secured. A pilot should consider this an essential part of any flight.
Securing and Servicing
After engine shutdown and deplaning passengers, the pilot should accomplish a post-flight inspection. This includes a walk around to inspect the general condition of the aircraft. Inspect near and around the cowling for signs of oil or fuel streaks and around the oil breather for excessive oil discharge. Inspect under wings and other fuel tank locations for fuel stains. Inspect landing gear and tires for damage and brakes for any leaking hydraulic fluid. Inspect cowling inlets for obstructions.
Oil levels should be checked and quantities brought to AFM/ POH levels. Fuel should be added based on the immediate use of the airplane. If the airplane is going to be inactive, it is a good operating practice to fill the fuel tanks to prevent water condensation from forming inside the tank. If another flight is planned, the fuel tanks should be filled based on the flight planning requirements for that flight.
The aircraft should be hangared or tied down, flight controls secured, and security locks in place. The type of tie downs may vary significantly from chains to well-worn ropes. Chains are not flexible and as such should not be made taught as to allow the airplane some movement and prevent airframe structural damage. Tie down ropes are flexible and may be reasonably cinched to the airplane’s tie down rings. Consider utilizing pitot tube covers, cowling inlet covers, rudder gust locks, window sunscreens, and propeller security locks to further enhance the safety and security of the airplane.
Hangaring is not without hazards to the airplane. The pilot should ensure that enough space is allocated to the airplane so it is free from any impact to the hangar, another aircraft, or vehicle. The airplane should be inspected after hangaring to ensure that no damage was imparted on the airplane.
Pilots Handbook of Aeronautical Knowledge Chapter 2:
Another important tool—overlooked by many pilots— is a good postflight analysis. When you have safely secured the airplane, take the time to review and analyze the flight as objectively as you can. Mistakes and judgment errors are inevitable; the most important thing is for you to recognize, analyze, and learn from them before your next flight.
I add a few items to my post-flight procedures. In planes with low-compression engines, I always do a runup before shutting down. That way if I didn’t lean enough on the flight I can clean the plugs before the next flight—rather than finding out in the runup area. I also refuel so I am ready to go for the next flight. I have a can of dollar store furniture polish that I use to get the bugs off of the wings and cowl.