@Martian1912 usually most modders will include an installation guide for their mods. For JE, the best mod pack is papagamer's modpack, available on Nexus.
I personally use mods for quite a few games (DA:O, The Elder Scrolls series, Total War series, Dawn of War series, the old Bioware games, The Fallout series and so on).
Yes, it takes a while to understand how they work for each game, but mods tend to prolong the life of a game (being a modification with some extra content or modifying the existing content, or even total conversions, basically making it a new game, with new gameplay mechanics).
Also, yes, it requires an absolute attention to details and to know what you are doing, if a mod is compatible with another and so on. It may seem overwhelming at first, but after a bit, when you get more and more familiar with them, installing mods becomes routine.
In the case of JE, installing mods is a simple matter to add the files in a certain folder and overwrite the original files. Most mods are not hard to install. The problem is to ensure compatibility between multiple mods. For JE, papagamer's modpack has pretty much all you need. and you can use just part of the modpack. It also provides the backup files for the original files in case that you want to remove the mod files.
Personally, i mod my games after a vanilla playthrough. I want to experience the game as intended and then try to see what the modders offer. Sometimes is really neat stuff (Civilization IV Fall from Heaven II mod comes to mind, though there are plenty others). Sometimes is just an item modification (visual or a new balance) or even what it can be considered a cheat item (i stay away of those, as they tend to be overpowered and basically remove any challenge from the game)
