I've been adjusting VW and Porsche valves for 30+ years the same exact way as I'm about to describe.
First thing is to print these instructions:
Locate top dead center by removing the distributor cap and rotating the engine clockwise (looking from the seat of the car towards the rear of the car) until the TDC mark is at the 12 o'clock position. The rotor should be pointing towards the notch in the rim of the distributor. If it's pointing anywhere else, try again. Use a large adjustable wrench to turn the pulley nut, which in turn will rotate the engine..
Once the rotor is aligned with the notch in the rim of the distributor and the TDC mark is at the 12 o'clock position, remove the valve cover on the drivers side of the engine.
The (2) valves closest to the rear of the car are for the #1 cylinder. Reach in and grab the pushrod, twist the rod and it should spin freely but not to loose. (Note:::: If you're running a 356/912 engine or a "stone" stock VW with aluminum pushrods, adjust the intake to .004 and the exhaust to .006 (The exhaust ports and corresponding valves are either closest to the rear of the car or closest to the front of the car. The (2) center rocker arms control the intake valves)
Next step, Rotate the engine ""counterclock"" wise one half of a turn. This will bring up the BDC mark to the 12 o'clock position. Adjust the #2 cylinder, it the cylinder next to #1.
Next step, Rotate the engine one half turn "counterclock" wise until the TDC mark is at the 12o'clock position. Remove the valve cover on the passenger side and adjust the #3 cylinder The (2) valves closest to the rear of the car are for the #3 cylinder.
Final step, Rotate the engine one half turn "counterclock" wise until the BDC mark is that the 12 o'clock position and adjust the #4 cylinder.
Install new gaskets on the valve covers and re-install.
The firing order for a Porsche or VW engine is 1-4-3-2-
By rotating the engine
backwards, the valve adjustment order becomes 1-2-3-4-
Cylinder identification is as follows.
#1 is closest to the rear of the car on the drivers side.
#2 is closest to the front of the car on the drivers side.
#3 is closest to the rear of the car on the passenger side
#4 is closest to the front of the car on the passenger side
FYI, the reason you rotate the engine counterclock wise during adjustment is to keep you from going from the drivers side to the passengers side and back and forth. This way, you adjust both cylinders on the same side at the same basic time.