Start with 2 girls in elevators (or shoulder stands) and have them hitch to a person (or persons) in the middle. Make sure their foot are overlapped and their thighs are parrallel to the ground.

Now have a girl in an elevator face them, bend and the waist, and place her hands on the middle layer flier's thighs.  The middle layers will support her and the shoulders with their inside hand, and place their outside hand on the top flier's lower back. 

On count the bases for the top flier will dip, the top flier will ride up at the waist, and gently stand up in a handstand.  Make sure she stays tight and squeezes her position. When comfortable have her do the splits for the finish.