Do Your Records Have an Itch You Can't Scratch?.
Scratching when done correctly provides color and an extra kick to any DJ mix. A simple way of explaining scratching is the sound produced when a sample of the record is played forward and backward under the stylus (or needle). The segment played could be any part of the song, for example a single beat, symbol, or vocal bit. When most people think of scratching it is the forward and backward motion they think of. There is nothing wrong with this interpretation but it suggests that there is little scope for variation. When first discovering the art of scratching many people are surprised at the multitude of variations derived from such a simple concept.
It is important to remember the idea of scratching is to keep the scratch simple to begin with. This can be done by selecting a simple scratch pattern or by slowing down the movements until you have the pattern fixed in your head. Don't get discouraged if your first attempts result in utter chaos. Stick with it and you will be surprised at how fast you pick it up.
One of the most frequent problems beginners have with scratching is the needle jumping. First of all you will need slipmats if you want to scratch. Slipmats are placed between the record and the platter; the most common are the felt types, which can be bought at almost any record store. A tactic used by some DJ's is to place extra material between the mat and the platter to further reduce friction, such as wax paper. Beware though because too little friction can be as bad as too much. One of the most common reasons the needle jumps is from improper hand technique. Because you are using equipment that is highly sensitive to vibration it is essential to keep you hand/wrist movement as smooth as possible. The key lies in hand eye coordination, but like most things practice makes perfect. Some records also might fit loosely around the center spindle, which will cause the needle to jump as well.