My El Camino is a well-massaged 'survivor" with the original fragile paint, not a true concours car, but I'll pass along what I've learned about care from years of reading and searching this and other detailing forums.
Any act of wiping or touching can induce fine scratches, so every effort should be made to reduce the possibility. I've used covers before on other vehicles, but since I store my Camino in my home garage, it often needs to be backed outside to make room for another vehicle that is in the bay. The mere act of installing or removing a cover has the potential for damage, so unless it's going to sit for months at a time and gets thoroughly cleaned first, I don't use one. I do drape a soft blanket over the hood and roof since I can remove and install without any sliding of the material over the paint.
Except for the very rare occasion when it gets really dirty, I don't do a conventional hose and bucket wash, as there's too much water running into places where I cannot dry it. If there's just a few days worth of dust, I'll use a waterless wash such as Opti Clean. I'll use a bunch of good MF cloths (my favorites are these:
Super Soft Deluxe Blue Microfiber Towels, microfiber detailing towels, buffing towels, micro fiber towel, detail cloth) so that dirty cloths make a minimum of contact with the paint.
Most often, my cleaning involves a rinseless wash.At home in the garage or driveway, I can do a rinseless just as quick as a waterless and I feel there's far less potential for any marring or scratching.
In any event, I highly recommend protecting your baby with a coat of wax. The microscopic layer of wax will reduce the tendency of dust or contaminants to stick to the paint and the reduced friction afforded by a slick surface will mimimize marring by a cover or any other wiping. in order to reduce the amount of rubbing, I prefer an easy-on, easy-off product. I've used a number of waxes, but my current favorite is Meguiar's #26 Hi-Tech wax since it needs less rubbing than most and doesn't change the appearance of the well-polished paint except for adding some depth, gloss and slickness. Despite my efforts at brevity, I've gotten quite wordy here, but I hope you at least have some answers to your questions.
Bill