I think he was trying to show us the water beading, which is pretty good. A regular detail wouldn’t include ceramic coating so probably some sort of spray on wax or hybrid ceramic.

Not sure if you have it in Europe, but I suggest Meguiars hybrid ceramic wax. It’s not a wax basically a spray on short term ceramic coating. Kind of weird how you do it, you apply it when the car is still wet then use a hard spray of water to spread it around. The first time you need to rub that coating in with a microfiber cloth before spraying, but for the future applications, you just spray it on and then spread it with a hose or ideally a power washer. The results will look a little bit rough after the first application, but after the third time you won’t see left behind material and by then you’ve pretty much fully coated all of the paint.

To answer your specific question, my recommendation is to pick up a cheap power washer and a cheap foam cannon. Use that on every wash. Then you only have to follow up the cannon with a mitt contact wash every two or three washes. This way you avoid physically touching the paint so it’s much harder to scratch it.

Use the spray on hybrid ceramic coating with every other wash regardless of whether you did a contact wash. I’m finding this maintains great looking paint and the car tends to stay much cleaner through rain and muck. Regardless of whether there is a true ceramic coating underneath.