1- open your game install folder
2- navigate to the modlib folder: .../DRAGON BALL Sparking! ZERO/SparkingZERO/Mods/ZeroSpark/Json/
3- extract the mod .json file of your choice there
4- open Jsonfiles.json in a text editor, it should look like this: "Default": ["Example1", "Example2", "Example3"]
5- edit out one of the Examples so it looks like this: "Default": ["Example1", "Example2", "GoDSatan"]
6- to add more mods: "Default": ["Example1", "Example2", "GoDSatan", "GoDSpopo", "GoDNappa"]