Replying to Throwing flips off bigger jumps

I recently learned backflips and flats last weekend I was doing my backflips and flats off decently small jumps. I did my backflips off a small kicky side hit and my flats on about a 15 foot small park jump with little kick too it. At my mountain they have now built about a 30-40 foot jump which I hope to flat and maybe backflip off I don't want to over rotate or under rotate when I throw it so if anyone has any tips to keep myself in control when I am flipping and how to throw my self that would be great. Thanks