Well all those fast detailers and waterless cleaners and waxes are good products but if you think as they claim that they wont scratch your car paintwork ... guess again! so, they're a good option if you wash the car first as Whizjet described.
Ceramic coating is by far the best way to go but if your car is not new and you have paint swirls and micro scratching you will need to remove them first as ceramic coating will lock them in to the finish. Now a dealer will charge you a fortune to treat your car to a ceramic coat but... its really easy to apply. It's a two application method but get this... you just wipe on the first product with the applicator sponge, it dries very quickly then you apply the second solution straight on top of the first in the same way. When dry you just buff it up with a micro fibre cloth. Job done! I do most of my cars and the finish is still working fine after ten years. And the cost, well you can get a kit for around £25 on the Bay! Not the £350 to £500 I have seen dealers charge.