User Created Levels, for others to play

Hello, I’m making a simple level builder game like Little Big Planet or Happy Wheels where the user creates levels and other players can play and rate that level. The level editor is going well, but how do I save and upload the level to some server so others can play it?

You serialize the level - as an XML file, a binary file, or some other format, and upload it to your server for others to download. https://unity3d.com/learn/tutorials/modules/beginner/live-training-archive/persistence-data-saving-loading