If you don't know how to balance on a gate I shall teach you.
Firstly the gate will have to be up ,and your pedals will have to be set. The way you set up your pedals are when they are both in the middle of your bike and are both the same height. Then you will put your prefered foot on the pedal that is closest to the gate. I put one foot on at a time and that makes it easier for me to balance. So once you have got both feet on the pedal you will then stand up and try to balance on the gate. If that doesn't work you will just have to keep on practising.