Touched image to reduce number

[schenker]

Hi, Im quite lost as to even where to begin. In a game that i would like to develop, there would be an image, sort of like a button with some numbers, say 15. Every time i touch on the image, it should decrement and show the updated value (14, 13 etc upon each touch action) on the image itself. Im not sure how to go abt. Any help or reference is greatly appreciated. Thanks so much!