I've seen these ideas around the net of giving baby socks/bows etc in egg cartons, and I've joined the trend. I'm egg carton obsessed. It's just how God made me. I've been felt bow crazy this past year too. Here are a bunch of tutorials for making these bows. I usually added elastic bands.
I also added some baby pearls. What girl doesn't need pearls at 3 months? Here is that simple tutorial.