If you want to move people – get under their center of gravity: it is never easy to move someone who doesn’t want to be moved. It’s even worse when they are bigger and heavier than you. Probably the most reliable means of doing so is to get UNDER THEIR CENTER OF GRAVITY. If you can do this it becomes MUCH easier to lift and move your opponent. From bottom you have to make your body and get down low. You will need some form of effective connection to your opponent – it’s no good getting under someone if you can’t stay there long enough to complete a move. A good place to start playing with this concept is bottom half guard. From there is relatively easy to burrow under an opponent if you can get an under theirs and the waist. Once under their center of gravity you will find it quite easy to roll side to side and carry them with you – that’s the location and feeling you want – like their center of gravity is floating over yours – once you can move an opponent you can or throw him.