I found this great you tube video that shows how to make a child size tutu with out sewing and I have used it to create a doll sized version .
I recommend watching this video for the method as it is the same for the dolls Tutu. If you can use scissors and can tie a knot or a bow you can make these tutus!
http://www.youtube.com/watch?v=B7aSPMEn7S0 The lady in the video's name is Julie and she has a great website
To make the dolls tutu I measured the dolls waist and tripled it to create the tutu. Then I used approximately 1/2 meter of tulle to create a really full tutu and less to create a less full one. I folded the tulle and cut it the so that the pieces I tied to the ribbon or the elastic were 6 to 8 inches long. You can add or subtract what you need depending on the desired fullness. You can also trim as you go if you find the skirt is to long.
I also created a tutu with out the ribbon by using a 12 inch piece of elastic which you tie into a circle. Then follow the same directions as above. The skirt took about 25 minutes start to finish and was really fun to make. This would make a great gift for any doll and ballet lover and an easy sleep over craft, one of the best parts is that the entire project can be completed for under $5. In the photo with the green tutu the top my doll is wearing is the Liberty Jane pattern for a tank top, in the free pattern section. Which I recommend!