Create an On/Off button on the stage

Is there any solution to transform this image to a sprite ?
30 Because I would like the On/Off button change to false by a simple click on it.

Sure! Get a picture of the watcher by right-clicking the stage and choosing "pic...". Then change the variable to false and get another picture. Then get rid of the watcher (unclick the check box), make a sprite, drag the two pictures in as costumes, and make a WHEN I AM CLICKED script that says SET [On/Off] TO (NOT (On/Off)).

Thank you !