Stack the newborn sized diapers 3-4 at a time, fanning them out horizontally and forming a spiral, fit inside the smallest cake pan.
Fill the cake pan with the diapers completely, then wrap a rubber band around them, securing them in the shape of the pan.
Remove the cake pan and set aside the roll of diapers.
Repeat creating a roll of diapers using the size 1 diapers in both the second largest and largest cake pans.
Place the largest diaper roll on top of the cake board/plate. Optional: tape this in place--however, be aware that this could damage the diapers.
Wrap the baby blanket around the largest diaper roll, folding the blanket to only be as wide as the diapers are tall.
Wrap a rubber band around the baby blanket, securing it in place around the diaper roll.
Place the second largest diaper roll on top of the largest.
Place the smallest diaper roll on top of the second largest.
Wrap the receiving blanket around the smallest diaper roll, folding the blanket to only be as wide as the diapers are tall.
Wrap a rubber band around the receiving blanket, securing it in place around the diaper roll.
To hide the rubber bands, wrap a ribbon around the diaper rolls, hot gluing or taping them in place. To avoid damaging a diaper, hot glue only ribbon-to-ribbon.
Add owl topper.
Tie a section of ribbon into a bow and affix to the center tier.
Decorate as desired. I added a onesie hanging off the top tier, some baby gear and a couple of sock/onesie cupcakes. To make the sock/onesie cupcakes, just fold the onesies in half, then roll them up, with an inside-out sock in the middle. Then, when the onesie is rolled tightly, fold the sock up around the onesie to secure it in place.