Attackers: commit the defender at pace and beat them with a change of direction and acceleration. Defenders: close down quickly, stay low and patient, and show the attacker away from goal.
Mark a 20x12m channel with a mini goal at one end and a starting gate at the other. The attacker starts through the gate with the ball; the defender starts in front of the goal and closes down as soon as the attacker's first touch is taken. The attacker scores in the mini goal; the defender wins by forcing the ball out of the channel or winning it cleanly. Swap roles every two reps.
The 1v1 is the duel every other drill in football is assembled from, and it is worth coaching from both sides in the same repetition rather than running separate attacking and defending sessions. The two roles are one problem seen from opposite ends, and a player who understands what beats him becomes harder to beat.
For the attacker, almost everything depends on the first touch. A touch that goes sideways or backwards lets the defender set his feet and the duel is effectively over before it starts. A positive first touch straight at the defender forces him to make a decision while moving, and a defender who is moving can be sent the wrong way. Pace at the defender is not recklessness, it is what creates the moment the feint can exploit.
For the defender, the mistake is almost always speed of arrival. Young defenders sprint the whole way and arrive with their weight going forward, which means any change of direction beats them. The correct pattern is fast while the ball is travelling, slow in the last two yards, side on and low. That is the difference between closing down and diving in.
The judgement worth teaching the defender is that he does not have to win the ball. Showing the attacker away from goal, onto his weaker foot, and delaying until support arrives is a successful defensive repetition, and scoring it that way stops players lunging. Most goals conceded from a 1v1 come from a defender who tried to win it and missed.
Save it to your private drills, then change the animation, adjust positions, swap equipment, or drop it into a session block. Or start from a blank pitch and build your own.