Im going to St. Anton, austria in 2 weeks and I really wanna try my first double backflip, any tips? I am very comfortable with singular backflips

Any tips or should I just try off a bigger jump

I want to grind my first rail and I want so good drills to practice

I would like to add some grabs for 360 or 180

Any tips for cork 7 ?also how big of a jump do I need to land it?