First lets get Unity ready.
Follow this ReadMe on GitHub and make sure you don't skip ANY steps.
Make sure you RESTART your pc after you installed GIT!!!
Once you are done with all of this you can now watch some of the videos that Laumania created on how to create mods.
YouTube Video's by Laumania:
How to find Player.log %USERPROFILE%\AppData\LocalLow\Laumania ApS\Fireworks Mania
Custom Firework Sound Collection (don't forget to credit the right license holders in your describtion)
Free 3D Model Collection (don't forget to credit the right license holders in your describtion)