Last Update: 6/7/2020
Steam
If you're playing on the steam version of Spiral Knights, getting your game's files is quick and easy. Simply right click on spiral knights > properties > local files > browse local files
And you're done.
Standalone
If you're playing on standalone, it's a bit more complicated. You need to go to your applications persistent data path.
On windows it's C/Users/Username/AppData(hidden folder)/Roaming/Spiral Knights
I don't know where it is on Mac, but you should be able to find it somewhere.
And that's it! You've found your SK directory. You can make all the modifications you want in here. Let's move on to step 1.
To get started you're going to want to download https://github.com/lucas-allegri/spiralview/releases
After downloading, just drag it into your game's directory and you have it installed. Double click it to launch it.
Open the model viewer, that's what you'll be using the most.
Retexturing an item is the easiest mod to do. All you need is an image editor. There are some good free image editors such as Gimp, or Paint.net.
Now all you need to do is go into your game's files and find the texture for the object you want to edit. Open it up and make the changes you want to make and save. It's easy as that!
The mod loader extracts .zips into your rsrc folder, so that's where your mods should start. After you do that, make sure you have 7-zip and archive all your files into that format. Some other archive formats work as well but .zip is the easiest. You need to also create a mod.json containing some basic info about your mod, head over to the discord to learn about how to structure it.
Head to #showcase in the discord to submit a mod. The site is updated weekly.