Sister twists are adorable for little girls! Not mention they are a protective style and can last up to 2 weeks.
I washed A's hair a couple of days before, and put her hair in several big single braids to stretch her hair out a bit. Once we were ready to style I took her braids down and used Giovanni Direct Leave-in to finger detangle her hair. I added a few cornrows on the side first, then I started parting small boxes in the back of her hair and working my way up. You can use unrefined shea butter on the twists, or whatever your product of choice may be.
Sister twists are very easy to do. You just part the hair out, split it into two sections, and twist each section in opposite directions, then start twisting them around each other. This is a great video tutorial on sister twists http://www.youtube.com/watch?v=ySdefk441Qk. I find sister twists last much longer than regular two strand twists. They have a much better hold, and much less frizz. I did these twists on dry hair. Not only do they add more length, but they minimized the amount of frizz A had. I'll show you a side by side comparison shot. Sister twists done on wet hair VS sister twists done on dry hair. If you want the thicker, curly twists, try doing regular two strand twists on wet hair.
We moisturized these twists every couple of days with some Giovanni Direct Leave-in. Add a bow and you're good to go! :)