First and foremost, make sure you have a diagram before removing the old belt. If there isn�t one under the hood, get out the pencil and paper and draw it out labeling the pullies and arrows pointing to the direction the belt travels on them. Save this paper in the glove compartment when the job is done for future reference. As far as replacing goes, it depends on the engine. Believe it or not, they are different amongst manufacturers, makes and models, so Bclear! If there is a spring loaded tensioner, you�ll need to turn the tensioner back to relieve pressure, and slide the belt off the tensioner pulley. Depending on the tensioner, you may be able to use a socket wrench with the right socket, 3/8� drive with socket wrench, or in some cases, you�ll need a tool that is meant for just this called a belt tensioner wrench. After it is relieved of tension, the belt can be removed. The new one gets routed the same, if you can�t remember, refer to your diagram. If you didn�t make one and can�t remember, listen closely and you�ll hear me laughing at you. Some belts require motor mounts to be removed and some are just plain nasty, such as the 1.9 motor found in Ford escorts. If there is no tensioner. Look for a bolt going through a bracket that the alternater or Power Steering mounts to. Loosen the bolt, pry back whatever components keeps tension, and replace the belt. Make the tension respectfully taunt and tighten bolt back down after the belt is replaced..