This is an intermediate to advanced submission that can be used when your opponent pushes you away in Side Control or Kesa Gatame.
The closer to the hips that you control the larger the pocket will be for your knee to lead in at the armpit. Make sure to base off the hand that is next to the hips and the foot that is based on the foot. This should resemble the feeling of a technical standup. Once you elevate your hips it should be a really easy transition.
Make sure that you insert the shin all the way up until the foot catches at the back of the shoulder. This will insure that you have a tight armbar. When you are in the elevated position make sure to situate your weight directly over your partner/opponent. This will make it difficult for him/her to defend by ripping their elbow to the floor as they will have to overcome your weight first.
The last thing that should be noted is that during most of this video I complete the armbar by holding the wrist with both hands and moving my pelvis/hips into the back of the elbow (like a traditional armbar). I highly recommend training this way for injury sake but keep in mind that while doing this in an MMA fight or a high level competition I recommend keeping the wrist behind the armpit as it will make the arm break before your back hits the floor. This will leave very little (if any) time to defend.
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