Sometimes after you wash your vehicle there is some contamination still left over. Before you go to polish your vehicle it may be a good idea to just run your hand lightly over the paint to feel for any rough spots. If you feel these spots now would be the time to get rid of them by using a clay bar. Just like with washing the car you do not want to do this in direct sunlight. It will be better if you wash and dry you vehicle outside then move it into the garage to clay the vehicle.
It is a good idea to clay your car at least twice a year. If you live in an area where there is a lot of industrial fallout or contaminated areas then claying the vehicle should be done more often. The more contamination that is in the paint the greater the chance you could introduce more imperfections in the process of using the clay. That is why it is so important to know the area that you live in and to keep up with washing the vehicle on a scheduled time frame.
The first thing you need to do is to decide on what type of lubricant that you want to use for the clay. There are two popular choices a quick detailer or a mixture of water and shampoo solution. Plus if you by the clay bar in a kit it may come with its own lubricant. The lubricant provides a slick surface for the clay to glide on. If you do not use any lubricant the clay will stick and mar the finish of the vehicle. Also bits of clay will be left and they may be difficult to remove from the vehicle.
I usually use a car wash soap. I will put one capful in a spray bottle and then fill the bottle with water. Normally the spray bottles I use will hold at least 20oz of water. If you decide to go with a quick detailer look for one that has some cleaning power but will not have any protection. The detailer will help loosen the embedded contamination from the paint and help the clay give great results.
Now to get started with using the clay bar. First you will want to wash and dry your vehicle. Next break off a piece of clay about the size of a 50 cent piece. Knead the clay until it is very soft and pliable. You can form the clay into a shape that will work on a flat surface. On an area of 18 "x18" spray some lubricant so that the whole area is covered. Then take the clay and gently slide it over the surface of the vehicle. Work the clay in overlapping passes. You can go left to right or up and down the vehicle. Stubborn contamination may require multiple passes with the clay and more than just the initial spray of lubricant. You will know when the area is completely clean because the clay will effortlessly slide on the paint and you will not hear it picking up any more contamination. Just take a clean microfiber towel and wipe the excess lube off of the vehicles surface. Continue these steps until the entire vehicle has been done. Once the vehicle is completely clayed then rewash the vehicle to remove any loose contamination or any excess lube which might have not been wiped up. This second wash should be very easy to do because the clay will have made the surface so slick that the water will sheet right off vehicle.
Here are just a few tips which may make going over the vehicle easier. When you move on to each new section of the vehicle reshape the clay so that you do not see any contamination on the clay. If you can not work the clay to a clean spot then toss out what you are using and break off a new piece of clay. Also if the clay gets dropped do not reuse it get another piece. Avoid using the clay in the sun because you do not want the lubricant to dry on the surface of the vehicle. Use a fine grade clay because it will not leave behind any marks on the vehicle that you would need to polish out later. Lube, lube, and more lube do not be stingy with it because you do not want to run the clay on a dry surface.
Now that the vehicle is completely clean and smooth to the touch you may be wondering what is next. Next up for your vehicle will be a good polishing. That is something I will cover in another article.