DIY--STD suggestions

I found this really cute idea on another website. I think its going to be a little bit more expensive considering the little custom magnets on the actual STD card but it's different twist from the ones that I've seen.

Was wondering if you ladies have any suggestions on how I can possibly get the actual magnet stick on paper without damaging it too much?

PIC
http://www.weddingbycolor.com/loislovesclark/milestones/121735

Any thoughts???