Detailing is the word that escapes you, lol. There’s a section on here called Detailing, and a whole host of reading in there.
As above really.
Get some basic kit set up, don’t go mad, there’s lots of stuff out there and lots of it unnecessary, or stuff that can be added later. The most important thing after basic kit, is a good wash and dry technique, and then perfecting it. Key to keeping swirls etc to a minimum, is pre wash, that’s the touchless stages of washing, such as snow foaming and/or citrus pre washing, and it can remove a lot of dirt without any contact with the paint, meaning much less to do at the bucket wash stage where there is contact with the car. A good drying technique is important as many swirls are inflicted st this stage, and key to that is final rinsing with the open running water hose which leave less standing water to be dried off. After that it’s a case of protection with a decent wax or sealant and again, a careful application technique to maintain the swirl free paint.
So look at basic kit, wash and dry techniques, protection, etc. watch some videos to assist.
As well as the thread link in the previous post, have a look here, there’s guidance on kit etc and some links to technique guides at the end of the first thread.
http://www.golfgtiforum.co.uk/index.php?topic=277318.0