Run Macro Automatically When I open a specific workbook

Hi Team,

I have a excel file lets call it it "smidgen"... I also have written an macro in the above mentioned workbook call "Magic".

What I want excel to do is only when I open the file that it runs the magic macro.... I don't want the macro when I create a new workbook or even open any other workbooks...

It might help at this stage to let you know that I use excel 2013...

Sorry Team, I think this might be the wrong section to add this to... However I will not post it anywhere else untill i get a smack from someone...