: For a step-by-step guide on creating your first item or NPC, refer to the tModLoader Modding Tutorial on the Terraria Community Forums. Requirements for Modding

Start tModLoader directly from your Steam library (do not launch standard Terraria).

If your request mentioned "develop" because you want to , here is the workflow for the 1.4.4.9 environment:

Go to "Download Mods" to find new content or "Manage Mods" to enable/disable what you've already downloaded.