1. Setup your Offline Server and practice:
http://pservero.com/ragnarok-online-server-guide-make-own-ragnarok-online-offline-server-guide-1/
2. Register to Hercules Forum http://hercules.ws/board/ OR rAthena Forum https://rathena.org/board/, To fix server bugs or error, to download & request (NPC script, custom item sprites, custom maps, patcher themes, Fluxcp themes, etc).
3. Use Google and Common Sense, to search and the easy way to find solutions and to fix your server errors display at map server or any errors/bugs related to your server.
- Example your map server error is "[Warning]: itemdb_search: Item ID 13414 does not exist in the item_db. Using dummy data."
- Type to google: "[Warning]: itemdb_search: Item ID 13414 does not exists in the item_db. Using dummy data"
OTHER INFORMATION:
1. Ragnarok Developer Tools: https://hostporing.com/clients/index.php?rp=/knowledgebase/24/Ragnarok-Developer-Tools.html
2. [Tutorial] How to Create Ragnarok Offline 2013 client: https://rathena.org/board/topic/84746-tutorial-how-to-create-ragnarok-offline-2013-client-tutorial/
3. How to set up your online Ragnarok server: https://rathena.org/board/topic/53369-how-to-setup-your-ragnarok-server-in-linux/