Women BWO fear on beam

[Gymnastforeverxoxo]

So I've been stressing about my bwo on beam. I need it for the next season. I have a pretty good ball walkover on the floor and I can do it on a floor beam and sometimes a low beam. But I need it on the high beam soon, does anyone have any tips for how to get a more flexible back or how to do a better back walkover on the low beam??? Any advice would be appreciated, thanks