foam board in black or white (I bought mine at Hobby Lobby for $5.99 minus 40% off with coupon)
a sharp exacto knife
sticky tack (optional for displaying)
2) Now take your exacto knife and follow that line.
3) Next lay out some scrap papers or cardboard and spray your foam board with the adhesive (make sure to get an even coat and take special care to get the corners. You don't want the edges to come off.
4) Quickly before the adhesive dries carefully line the photo up on the foam and flatten and smooth with a clothe (or your shirt sleeve if you're like me). You can adjust the placement some but not a lot so take your time getting it in the right place the first time.
5) Like I said the adhesive is pretty awesome and dries quite fast so you can basically hang them up minutes after finishing. This is perfect for super impatient people like me. :)