Open the T.I.T.S game folder
Go to the `mods` or `custom` content directory
Create a new folder for your throwable
Add the throwable asset files to that folder
Include the required config or manifest file
Set the item type to throwable in the config
Add the icon, model, and any effect files
Match the file names exactly as required by the game
Save all files in the correct format
Launch the game
Open the mod or custom content menu
Enable the custom throwable
Test it in-game
Check the logs if it does not appear
Fix any missing paths or invalid file names
Reload the game after making changes