I finally found it:
HOW TO GET YOUR MONEY?S WORTH FROM A SELF-SERVE CAR WASH
USING TIRE CLEANER/ENGINE DEGREASER (low pressure):
For best results, use the tire/engine cleaner first while the tires or engine is dry. This will allow the chemical to work without being diluted by water. After applying, let the chemical stand as long as possible while washing the rest of the car. The longer it soaks, the better it works.
USING PRESOAK (low pressure):
Presoak will help clean your car if you do not want to brush it, or if it?s very dirty. Just spray it on from bottom to top. This lets the dirtier areas soak longer.
USING
SOAP (high pressure):
Select
SOAP, then wash the car back and forth in sections to avoid missing areas. Hold spray a few inches from tires to clean whitewalls and lettering.
USING FOAM BRUSH:
Always wash dirt off car and brush before use. The foam brush will not scratch your car, but dirt will. Scrub lightly on paint from top to bottom. Brush the very bottom last to avoid picking up dirt or mud from the fender wells and scratching the paint.
USING RINSE (high pressure):
Select RINSE, then rinse off the
soap from top to bottom.
USING WAX (high pressure):
Select WAX, then apply from top to bottom. The excess wax can be left on if you towel-dry the car, but should be rinsed off to avoid heavy spotting.
USING SPOT-FREE RINSE (low pressure):
Select SPOT-FREE RINSE, allow 10 seconds for line to clear, then rinse from top to bottom, pushing the water across the hood and roof. You can switch directly from WAX to SPOT-FREE, but always rinse off
soap before using spot-free rinse. Spot-free is not a treatment or coating, but is very clean water that does not leave spots behind, so it should be the last step in the wash process