This is step three!!! Go down to the first Bugaboo post to get step one. And don't laugh at my incandescent whiteness!
All the rest of the pieces and placement should be obvious. I highly recommend some machine washing with soap and drying in the sun.... and you need those doohickeys that go on a valve stem for the bikes. I found the owner's manual by Googling bugaboo frog owner's manual- I'll print that and put it in the box for you.