How do i change the image of a push button?

I have a Push button which resets the level to the start again when its pushed. Its a grey box and I cant work out how to put a image over it.

I tried putting a Image in the "create Container" properties option but I think that's for something else?

I tried putting a image over it but the push button will go on top.

So why not just use the image as a button?

So why not just use the image as a button?

With an animation to differentiate the state. And bolean variable IsEnabled=true/false