A month is not really long enough to get "in shape", depending on how not-in-shape you really are.
It´s hard for a normal body typed girl on a team with lots of athletic girls, from my experience, to see your real body shape and not being to hard an yourself.
I´ve lost a lot of weight over 3 years (thank you, cheerleading), gained some (just a few pounds), lost some.
For loosing weight things like running or spinning help really quick. Everything you do additionally to your cheer practises will help.
There´s an app for smartphones, it´s called something like Daily Ab Workout. This helped me a lot.
Showing discipline when it comes to everything with sugar or chips will help, too.
Good luck!