If you have a vinyl wrap over the entire car, we do not recommend the use of Three Way.
Make sure the vehicle you're decontaminating is in the shade and the paint is cool to touch. A well-ventilated area outside in the shade is ideal.
Spray Three Way directly onto the painted surfaces (don't stress if you get it on headlights, plastics, etc, as it's 100% safe for all of these surfaces) 1 panel at a time, and allow 1 minute for the purple reaction to begin. This reaction is the ingredients in Three Way reacting with the iron particles on your paint, and safely breaking them down so they can be rinsed away. You will notice this reaction will be stronger on the bonnet, roof and rear of the car, as these are the panels that will see most of the fallout on them through normal use.
After 1-2 minutes (no more than 3-4 minutes), rinse the panel thoroughly. If you're worried about water drying on the panels, dry the panel before moving on. Move onto the next panel and use the same method on each subsequent panel, until the whole car is done.
After you have washed and rinsed the vehicle after using Three Way, dry the whole vehicle. It's good practice to run around the vehicle with a small battery powered blower if you have one, and blow all of the water out of the nooks and crannies like around the wing mirrors, behind door handles, wheels and tyres etc. It's also a good idea to quickly dry the door jambs, wheels and tyres with a couple of Dirty Deeds cloths.