Sorry to keep things delay about button tacks that I promised to show how to use it. Here I am..
Gather any size of buttons that you want to use it for your cork board. Grab a Hot Glue Gun... and a couple of tacks. ( you can find it from Dollar General, Wal Mart or any office stores)
(Ingore my dirty keyboard, haha.. )
Glue tack on back of the button. Try not to put too much glue thur the button holes and it will drain thur or you 'll burn your fingers.
It happened to me many times to burn or stuck with glue! Ughh..!
Ta-Da! You are all done. It's so easy as a pie!
Another idea for you. My sister used old earrings that you can find it from garage sale or re-sale shop. She ripped the clip-on from the earrings and put a tack behind of the earring. Ta-Da.. !