Even if you don't have a great hand-me-down framed bulletin board, you can whip up one of these.
I started with the frame and bulletin board from Little Moore's room:
I pulled the cork board out of the back, and took off the old fabric. If you're starting with a plain frame, take out the insides, and cut some cork to fit. If the frame isn't the right color, this is also the time to paint it.
Using a staple gun, staple the fabric in place, and then pop back into the frame, making sure that it is right side up (if your fabric is directional).
Use large staples to staple the frame to the cork board. Make sure to secure it well.
Then hang it up on the wall! I was able to use the existing hardware on my frame, but you want to make sure that you use hardware that will fully support the weight of the frame, cork, fabric, and whatever you pin on the board.