For Clay Barring its really a simple process and NOT a taboo subject..ITS dead easy..
There are loads of good You Tube vids....will find a `Good one` and put the link here in a moment.. Here we go....
Car Claying - YouTube
1) Just wash the car thoroughly, no need to dry...
If you buy the Meguairs kit it comes with a detailing spray that acts as a application spray. Found this kit best value for money as it comes with MORE clay bar
2) Pull about a quarter of the clay bar off ONE of the bars (KIT COMES WITH 2 BARS) and work this into a flat shape, about half the size of a fried egg!
3) Work a panel at a time, spray with the fluid and then rub the clay bar over in a back and forward movement until it becomes very smooth..u will see as you use it
4) WIPE off with a good quality microfibre cloth to polish as you go
5) After working over the whole car, finish with a good coat or two of a good quality wax.
6) ON NO ACCOUNT If you drop your clay bar you MUST throw it away..otherwise it will pick up grit, which you will work into your paint..
Your car paint will come up like Glass....Have fun
Let me know how you get on....... Pete