How do you replace the serpentine belt for a 1993 Mazda Protege?

you have to loosen a bolt on the front of the AC compressor, I think its a 12mm. You loosen it and the the AC compressor will then be able to rotate downward, sometimes the compressor gets stuck with age and you might need to tap it down with a mallet. Once the compressor rotates downward the tension in the belt will be gone and you can change the belt. Then tighten the same bolt until you achieve the desired tension