How do I learn to mod?

The community has made serious strides in modding the Souls games. However, as a whole, the games are not mod-friendly. There's no one-size-fits-all SDK, and each aspect of the game has a different tool for modding it (some don’t even have tools). The recommended steps for beginners are:

  1. Read the Game Engine & File Formats article to get a background.
  2. Go through some tutorials, especially the ones in the beginner section.

I used Yabber to add/edit a file, but it's not showing up in game, what's going on?

Whenever you unpack a game archive with Yabber, and then edit or put a file inside that unpacked folder, you need to use Yabber again on the folder to repack it back so it can be read. Also, if you added a file, you will need to edit the .xml file that Yabber created to include the new file in the list of entries, or else it gets ignored when you repack.