1 on 1
Defender X1 starts and stays head on the ball. Force dribbler O1 to change directions as many times as possible is his backcourt, but most importantly contain him (sprint and recover as needed).
As O1 enters his frontcourt, keep him on one side if possible, or let him go from one side to the other, just not ball in the middle, where there is no help defence with everyone in denial.
Finish by chesting O1 with hands out and up, forcing a tough shot.
2 on 2
No long skip passes. X1 denies with one hand, other forearm and fist on O1, but lets O1 catch the ball on the short side. However, X4 doesn't let O4 throw the ball in on the short side. On the inbounds pass, X4 jumps below the level of the ball (let them throw it back to O4).
X4 then gets on and up the line of the ball when O4 gets ahead of the ball (ball-you-man). X4 can fake at O1, and will switch if X1 gets beat.
3 on 3
X1 and X2 have their backs to the middle of the floor. If O1 and O2 try to screen, the defenders come back to back, switch as needed.
On the inbounds pass defenders get below the level of the ball, on and up the line, faking at the ball.