Sharing ethernet internet

[Superman041]

I'm running Mavericks and trying to share my ethernet internect connection so that my iPhone will connect to it's Wifi. Everytime I click to share to computers over Wifi, it turns the sharing off. As shown in the picture.

 

[The-Pro]

you will need to click the box on the left where it says internet sharing. It will then grey out the "to computers using: ..... etc" part.
You will notice the wifi status in the menu bar changes from the signal strength indicator to a grey solid with an arrow pointing up.