Probably the most common question I get asked, is how to remove the serpentine belt. Jeep didn't use a spring tensioner like most other vehicles. (Note that some later Jeeps did have a spring tensioner) There's a manual adjustment screw to adjust the belt tension.
The adjustment bolt is located on the power steering pump. Since it doesn't get used much its best to hit it up with PB Blaster several times a couple days before you actually get ready to change your belt.
I'm working on my YJ, TJs are similar but the adjustment is on the side instead of the bottom, the procedure is similar though.
First thing you need to do is loosen all the bolts on the power steering pump so it can be moved freely. Typically people miss the ones on the back, there are two. The wrench in the picture below is on the bottom bolt, then there is one more above it. Remember you are only loosen these bolts so the pump can move, DO NOT remove them.
On the front, you also need to loosen the top bolt.
Now there is a jamb nut on the adjustment bolt as well that must be loosened. Now be gently with the adjustment bolt, if it doesn't turn freely, work it back and forth some while spray it with PB Blaster, you don't want to break it. Just back the adjuster off enough to get the belt off. You should NOT have to pry on anything to remove the belt, you can damage the pulleys and/or the belt.
Now keep in mind that since this is a manual adjustment it is possible to over-tighten the belt, which can lead to belt failures, and bearing failures in other things like the alternator, idler pulleys, etc. Take the longest stretch of belt, place a straight edge on it. You should only be able to push down on the belt roughly 1".
Since not everyone pays attention to how the belt comes off, I'll share some common belt routings. Don't take that wrong either, because I'm also guilty of this, I've run around with my belt on wrong for the past 2 years, wondering why my belt squeals anytime the alternator really starts to charge. Once I had the belt on correctly, the problem went away, imagine that?
Note that in all these images, if a separate image isn't displayed for a non A/C routing, or non P/S routing, the routing is the same, Jeep just added an extra idler pulley in to compensate for the lack of A/C or P/S.