Use the claybar if you are cleaning a car without wax. If you keep up the wax, you will never need one. Clay bars are good but they wear out the paint much more rapidly than just proper maintainence.
92 TripleBlack's cleaning tips

Mostly from other corvette owners)
-Wash car with car wash. Always wet down panel before soaping up. Water is the lube that keeps grit from scratching your paint.
Use real car wash. Dish soap and other soaps remove wax. Use a sheepskin mitt or other sheepskin cleaning instrument. The shag wisks away dirt into the fibers so you don't scratch as you would with a sponge.
-Rinse using a hose on medium without the nozzle. The car will dry itself much more rapidly than with a nozzle. if you do this, the water doesn't spray, so you don't have all the small dropplets all over the car.
-Dry with 100% domestic cotton towels, not the crap they sell in the autoshops. You can also use "The Absorber" which is what I do. Just rinse it on a regular basis so it doesn't keep any remaning grit on it scratching paint. Don't use a blower. It will put dust onto the car which will then scratch when you wax it.
-Wax using a good carnuba wax. This is a very hard wax and will last. Don't use polish. Polish will remove what is there and won't build layers.
If waxing for the first time, do it at least twice. Then wax say every 1-2 months, more if it is hot or there are lots of polutants in the air such as dust, pollen, road salt, etc. Use again the same cotton towels to take off wax. Leftover ones from drying are good. For wax, I use Zaino Bros. if I am going to put an inital layer on or if it is my vette or infiiniti as they are black and need the best wax. The mada gets a spray on when drying wax from Eagle one. Easier to put on, it doesn't last long. But I use it every time I wash so its good enough. You could get tennis elbow waxing a mada the traditional way.
-Windows- Don't use Windex. It has ammonia which will discolor window tint. Use a glass cleaner like glass perfect or Stoners to clean. Wipe side to side on the window on the outside, top to bottom on the inside. If you see a streak, you will know if it is inside or outside.
-Bugs- I power wash first and then use car wash to kill these. If you have wax on , you will be fine. Dryer sheets are supposed to help removing them. Some people put Pam cooking spray on the front also to fight bugs. Don't use those pads. Instant paint scratches.
-Tires-Use a UV tire protectant. Armor-all and other silicon based products will magnifiy the sun and promote dryrot. They also attract dust and are hard to remove.
-Interior- Use approved stuff, not armor-all. See tires for reasons. Most plastic panels will clean with just water. Use some good interior cleaner on plastic that won't clean with water like Meguires. For carpet, I vaccumn but I will also use my Hoover home carpet shampoo machine for spots. For leather, a good leather cleaner works well to preserve. I use Meguires leather wipes for ease of use.
-Wheels Wax them like you do the other paint. This will make the brake dust come off easy. Don't use the same applicators you use on the paint. Wheels are dirty and will get them really dirty quick. Use the old ones on the wheels rinsing frequently. I power wash them and it kills most of the dirt right off the bat.
Don't forget to clean the door sills, inner tire wells, and engine compartment. I power wash all these.
Hope this helps!