I have used the following clay kit made by meguiars
Smooth Surface™ Clay Kit
http://www.autodetailingsolutions.com/Clay%20Bars.htm
Here are some suggestions to get the most out of claying your car
1) Wash it first with a kitchen type dish soap to remove as much of the old wax as possible
2) I suggest claying your car in the garage our in the shade to avoid direct sunlight
3) Take a brand new clay bar and tear off around 1/3 of the bar and shape it into a shape that will fit your hand well such as a small panckae around 1/4 inch thick.
4) Use plenty lubericant on the area you plan on claying.
5) Only clay a small area at each time. If you notice dirt in the clay fold it back into a ball and then reshape it again and keep claying
6) When you start claying an area you will notice some slight resistance as you move the clay bar back and forth or in a circular motion you will notice it will start moving easier as it removes the debris from the surface of the car. When the surface feel like glass as you move the clay bar back and forth that area should be clean
7) If you happen to drop the clay bar on the ground or any other dirty surface throw it away and tear off a new piece. Othewise you could scratch your paint if there is debris or major dirt in the bar as you rub it back and forth
8) When you are finished claying just wipe off the residue with a microfiber type towel and begin to wax your car
Even brand new cars need to be clayed in most cases.
