When detailing it's always best to tackle the dirtiest areas first. The very reason why we start our big details with wheels, under arches and engine bays. During the exterior contact wash stage however, we always begin with the cleanest areas of paintwork, to prevent dragging contaminants over from the more soiled areas and risk inflicting swirl marks. There's actually a specific order we follow to ensure the safest possible swirl-free wash, and here it is…
As we all know, you only contact wash after carrying out a thorough pre-wash to remove the worst contaminants. For contact washing, always have two buckets; one for clean water (to wash out your mitt) and one for your car shampoo.
Start by filling your buckets, then drop around 2-4 capfuls of Lather car shampoo into your wash bucket and froth up using your pressure washer lance.
Load up a clean wash mitt with suds.
Start with the middle of the roof working your way to edge, this will spread the suds more evenly. Always wash in straight lines rather than a circular motion, this will cut on the risk of swirl marks.
Now you can tackle the windows, start with the windscreen and then on to the sides. Leave the rear window for now.
Move on to the upper sides, these will be far cleaner than the bottom half. Again, straight horizontal lines, working from the top downwards.
The bonnet is next up, working from the middle of the top and working out.
Now move on to the dirtier areas, starting with the front bumper.
Next the lower sides can be cleaned, again starting with the top of each area.
Finally, complete the whole of the rear - the dirtiest area of all. Start at the top and move down.
Now you can rinse the vehicle and move onto drying or full decontamination. Simple.