OVER UNDER MOVE DETAILS
First, you maintain good posture. As, your opponent opens up his leg, you maintain contact with your elbow on their leg.
Once his second leg opens, you connect your elbow to his leg again.
Your other arm scoops his leg on your shoulder while you still maintain good posture.
That same arm that scooped the leg, you want to make sure you are reaching your opponents opposite shoulder or as in the video you are grabbing his gi collar.
You want to try and get his knee as close to his face, making it really uncomfortable for your opponent.
As all this is happening, you are starting to rotate forward, in order to pass his guard.
And you finally end up in cross body.
You want to secure your opponent with one hand blocking his hip and the other arm and hand blocking his head so that you keep him secure. It’s also good to be on your toes to add more pressure to your opponent.