Gentle Snow Foam [GSF] - Neutral Pre-wash Foam - Koch Chemie

Add a little Green Star if the vehicle is really dirty.
You can wash your vehicle with the foam as well, you just won't get any shine or streaking like with the Nano Magic or Ceramic Effect Shampoo.

Foam cannon: put about 30 ml of Snow Foam in 1 l of water and cover the vehicle with foam using a foam sprayer.
Active foam: put 10-30 ml of Green Star in a pre-mixed solution of Snow Foam.