Go to the Publish/download games. Click Publish project that allows secondary use. Pick the game/file you would like to upload, then click on Download(Receive) To get your Key.
Then tell your key to miiverse. To download go to Download (Receive) Using public key. Find a key then enter it :)
You might want to consider using a string variable in your program to make it more efficient. The code would take up less space as you wouldn't have to copy & paste "your puppy is enjoying his treat!" 3..4..65 times. You could just reference the string. Then you can also edit/update your message once, instead of 3..4..65 times.