SMLHelper is a complete library that helps you out on your Subnautica modding adventures by making adding new items, changing items, adding models, sprites a LOT easier.
Check out the wiki page for details on how to use it.

We would love to have people contribute to SMLHelper.
To get started, first fork the repo and then clone it to your local environment.

• As of version 2.8, SMLHelper has been updated for QModManager v4.0 and uses HarmonyX.

• As of version 2.2, SMLHelper is now using the publicized versions of Assembly-CSharp.dll and Assembly-CSharp-firstpass.dll (the originals being located in your Subnautica_Data/Managed folder).
  To create your own publiciezed DLLs, you will need to download or compile the Assembly Publicizer and follow the instructions to convert the original DLLs into Assembly-CSharp_publicized.dll and Assembly-CSharp-firstpass_publicized.dll.
  You will need to copy these DLLs into the Dependencies folder of the solution before you can build it.

Then, load up the solution, make your edits, then create your Pull Request!