12. ALWAYS read labels.

(Image Source: autodetaildoctor.com)
In the world of car cleaning, what’s good for one area is not good for another. You can’t use tire shine on your paintjob, and applying leather conditioner to fabric upholstery would be a nightmare. Products you use on vinyl dashboards and doors often can’t be used in any other area. If you don’t want stains, scratches, oily messes, and costly damage, research your products. Pay attention to what you’re applying, and where you’re applying it.