How do you tighten a squeaky belt on a 1996 dodge neon?

The usual culprit is the a/c-p/s belt.the alternator belt is a ribbed design, & usually doesn't give trouble. You need to use a 1/2" breaker bar in the square hole on the P/S bracket. Loosen the other bolts on the bracket, use the breaker bar to applt pressure to tighten the belt. If the belt has been noisy for a while, it is usually glazed, & should be replaced with a new one. Just remember to re-tension the new belt after it has run for a while, or you'll have the same problem with squealing.