Networking basics in just 4 steps.

Starting with an empty game project:

1. Create a Player Controller in the Scene Hierarchy
2. Right Click onto your controller game object => Create Prefab
3. Create an empty GameObject
4. Add Component "Network Helper"
5. Move your player controller prefab into the Network Helper inspector field
6. Delete your player controller from your **scene hierachy.**Now if you hit play, you can join via second instance via the networking icon in the top right and have a basic functioning multiplayer!

Referenced API

NetworkInstanceNetworkingGameObjectInstanceNetworking