Inspector > Add Component

By default, when you create a new MonoBehaviour component, it is added to the menu under Scripts/{namespace}/{component} and gets jumbled in with a lot of other random stuff from packages you have imported.

Default Example

namespace PlayableDesign.ThriftShop
{
    public class CameraController : MonoBehaviour
    {
    }
}

Menu

Yuck!

AddComponentMenu

Instead, you can create a custom folder at the top level of the context menu in the editor using the AddComponentMenu attribute.

Better Example

[AddComponentMenu("Custom/" + nameof(CameraController))]
public class CameraController : MonoBehaviour
{

}

Menu

Best Example

Even better, I like to use dashes as the folder name so that my components are always on top.

[AddComponentMenu("-----/" + nameof(CameraController))]
public class CameraController : MonoBehaviour
{

}

Menu

Enjoy!