What is the proper way to mix botox?

Well I work in a Dermatologist Office in NY and the way I mix the botox for hyperhydrosis and for therapeutic use is to fill a syringe with about 2.3 - 2.5 cc of saline solution, then that goes into the botox vial. Swirl the mixture and let it sit for about 3-5 minutes, you just want to make sure there aren't any bubbles in the bottle. Then each vial should fill two 1cc syringes. That's it !