How To Slide the Buttons in Windows Phone?

2) Add event to the object.

3) Use this event to control the animation.

You can read clearly about animation in MSDN.  

Refer : 1) Creating an Animation in Procedural Code

             2) Animation Overview : MSDN

I am not sure how animation works in Windows Runtime, but what you need is to change the dimensions of the control. A quick tip would be to change the margin (left property) and update it to make sure that the button floats over the maximum right side. 

 

Did you try anything, Google search or a small piece of code in Windows Runtime?