In an optimal setup, each group would have 14 cones. Person responsible for either losing the ball out or to the defender becomes the next defender. For this practice, add the limitation that players must hold the ball for at least two touches, to encourage players to control the first touch. This will give them the idea of possibly beating the defender themselves, rather than immediately being able to pass responsibility off to someone else. Another option is modified Keep-Away in which every player but one or two has a ball, and tries to stay in the grid without having their ball stolen by one of the players momentarily without a ball.
Defender has to make a legitimate takeaway to convert the other player into the new defender.
Directed Warm-up Phase Send everyone the length of the available practice field and back two or three times, with each player to go as fast as they can with the limitation that they must touch the ball at least every third step. Use standard straight-ahead dribbling technique. Pull ball under the body with the sole of that foot, pivoting on the other foot. Do quick acceleration cut with the outside of the foot, pulling ball along so that it remains in contact with the dribble foot. Space players along the field with plenty of room between players, and have players head towards a row of cones, trying to make a 180 degree turn as close to the line as they can and still do maintain control.