Image to gif video animation

Hello ,
i want this pic in the attachement , to look like water dripping from it , like its waterproof ,
example : water dripping on the window , that slide down the surface ,
so that water drops should look like it sliding on the notepad , if you have any question feel free to ask .
and better if you show me a demo on an empty layer or something for better chances .
p.s : you can remove the pencil , i want only the notepad .