For this step you will need approximately 30 diapers, your dressed-up cake board (or plain board), curling ribbon (any color, it will be used to tie the tier together and will be hidden, if you are using a light-colored wide ribbon then use a light-colored curling ribbon so it won't show through) and ribbon cutting scissors.
Lay down your cake board and start standing your diapers up around the perimeter of the board. When your two ends meet, start filling in the middle as shown:
When your board is full, take your curling ribbon and tie VERY LOOSELY around the diapers. (you will be stuffing more diapers inside, so make it very loose)
Cut off the extra slack of ribbon.
Will look similar to this when tied (your ribbon may look looser, this is okay):
Now, start filling in the tier with the rest of the diapers (using a total of 30 give or take) until the tier is round, tight and full, being careful not to break the ribbon. (don't worry if this happens, just tie again and make looser next time) Tier will look like this when done:
