A basic escape/transition from Side Control into Guard (Half or Full).  

Remember to only attempt this move when your opponent does NOT have the hand next to your hip.  This works really well with the people that control over your body, under your shoulder and drive their shoulder into your face.  This is a very common (and uncomfortable) position.

When this happens try to make as much space as possible with your hips.  Your opponents shoulder in the face can make getting a lot of space difficult but thankfully you do not need a lot.  Once you have made a little space insert that knee into your opponents hip.  Notice I drive to drive it far across.  I do this for two reasons.

The first reason is that you will be able to use the shin across your opponents hipline as a great shield to take weight and pressure off of your body.  This will make it much easier to banana your body (push away with your shin and arch your back).

The second reason is so that I can attempt to drape my leg over their leg in the back.  This gives you a little bit of control over what transitions that can make, gives you some sweeping options from Half Guard and it puts a speed bump in their game if they decide to try and bail to standing (although the leg across the back does most of these things too).

The banana of the body will be the hardest part.  Make sure to use your shin and your whole body in this movement.  If you watch the video you will notice that I have a good bit of body angle.  Make sure to move your body in the plane horizontally and not vertically.  There should be very little to no control in that plane and if you think about it, arching your back into the mat doesnt make any sense.

If your opponent refuses to let go I highly recommend pushing up on the face with both hands (some people think this is a dirty move, I think it's good grappling) or use the forearm like I did to bar the face away, create leverage and break the grip.

And please, for the love of all things grappling PLEASE get the underhook.