Need Help with C#/Unity Uploading Saved Level files from Game Level Editor to Steam Workshop

I just finished developing my latest video game "Zombie Ballz" which features a built-in Level Editor. The level editor currently saves files to the player's installed game directory in a sub-folder named "Custom Levels", but I would like to make it possible for players to share their saved levels with other members of the Steam community. Everyone says that Steam Workshop is the answer, and boasts about how easy it is, but quite frankly... I don't understand API, and really need someone to take my hand and walk me through this step by step. What would really help is a script that does all of the work, with an explanation of how to use the script in my own code. I have found scripts like this online, but have no clue what to do with the script, how to save it, or how to implement it into my game.