About a week ago I decided to finally try my hand at making a baby tutu, and I was amazed at how simple it was. I had glanced at several tutorials but really this doesn't need a tutorial.
Materials are simply 2+ yards of soft tulle (or a few spools of tulle, but I'm cheap and it's less expensive to get it by the yard), scissors, some elastic long enough to go around their waist and a needle and thread or sewing machine to join the ends of the elastic.
You simply take the elastic and sew the ends together at the right size to go around the baby's waist, take strips of tulle, double it up and knot it around the eleastic, and keep doing this until you have a full fluffy tutu.
Then you let your baby loose in the yard to frolic like a little fairy in your garden. ... or not.
Lorelei seemed to love her tutu. She kept running her hands through it and fluffing it up. Hooray for happy babies!
There are tons of tutorials online for tied tutu making. One decent one is here: http://grosgrainfabulous.blogspot.com/2009/05/midsummer-nights-dream-tutu-tutorial.html