It took me awhile to master the flip. Suffice to say I inhaled quite a bit of water for the first few weeks. (Ahem. Months.) As TG mentioned, it's all about preparing your breathing.
After choking and sputtering for long enough, I decided to move into a slower lane while I was learning to flip - namely because I found it easier to perform the flip slowly at first, so I could nail the technique before I sped it up. It really is a lot like doing a somersault; with the exception you have to expend energy pushing away from the wall and learn to control your breathing.
I'm sure you'll have it down to a fine art in no time.
