Instructions:

Step One: Quite the long materials list, eh? That's why I love this pattern... you don't have to mess with elastic! Ok, it is important to pre-wash your fabric. Otherwise, when your baby poos, pees and spits up on his/her nice new pack n play sheet and you go to wash it, it will SHRINK. It would be an utter waste of your 15 minutes. On the other hand, you don't want to sew your pack n play sheet too big, because nobody wants a saggy pack n play sheet... particularly the American Baby Association. So, do whatever tweaking you need to do in order to get your pack n play sheet fitting perfectly snug :)

Cut out your pieces. My preferred fast, and accurate way is the snip and rip method (see video for demonstration in my Ruffle Apron Tutorial). Rip out the large 49"x26.5" piece first. Then rip out two 29"x5.5" pieces for the side panels. I set my pack n' play mat in the back so you can see for comparison.