The implementation of the steam workshop in Toilet Flushing Simulator requires the user to make sure of a lot of things on their end are prepared for uploading
The basics

• You will need a 3D model (.fbx .obj, etc)
  
• You will need said 3D model to include a basic texture
  
• You will need a name for the model to upload

The workshop menu can be located by pressing the green toilet icon on the main menu of the game

Once you have opened the steam workshop submission menu you will have to input a few simple details about your item and the model itself.

• First, press the model upload button in the top left of the menu, this will open a window for you to select your model.
  
• Second, enter a name for your custom flushable, this is required as it contributes to many aspects of the item in the workshop and in game!
  
• Third, enter a description of the custom flushable, this is also required as it is a main aspect of the workshop page for the item!
  
• Forth, you must press the "Save" button, this will remove the UI for a moment to take a screenshot to be used for the workshop page. THIS IS EXTREMELY IMPORTANT AS IT ALSO SAVES ALL ASPECTS OF THE ITEM TO BE SUBMITTED TO THE WORKSHOP!! IF THIS IS NOT PRESSED YOU MAY SOFT-LOCK THE MENU OR CREATE AN EMPTY WORKSHOP ITEM!!
  
• Finally, after pressing the save button you can safely press the "Submit" button, this will let you know it is uploading and once it is completed will display "SUCCESS!" and a button to go back to the main menu.

PLEASE NOTE: YOUR CUSTOM FLUSHABLE IS NOT AUTOMATICALLY DOWNLOADED AND YOU MUST GO TO THE WORKSHOP TO DOWNLOAD THE ITEM! IF YOU ENCOUNTER AN ERROR THE MENU MAY STILL DISPLAY "SUCCESS" BUT AN EMPTY OR BROKEN ITEM MAY APPEAR, THIS CAN EASILY BE DELETED FROM YOUR WORKSHOP ITEMS IN YOUR ACCOUNT!!

If you encounter any issues, please comment below! another important note is that the custom flushable requires a texture or it may cause errors when uploading.