In the video clip below Tom Mura from World Class Coaching diagrams and explains a great 1v1 drill that transitions to a 3v3 drill.
The setup is fairly simple. Begin by creating three lanes approximately 12 yards wide using flat markers that allow balls to roll over easily. Place a goal and the end of each lane and some sort of obstacle in the middle (flag, cone, mannequin etc..)
In the first part of this exercise, place players in each lane with players at each goal. The players will begin dribbling towards the obstacle. When the reach the obstacle the will make a move around the obstacle and continue dribbling to the other end. You may allow the players to make any move the want or you may dictate the move that you want them to practice. Be sure to make sure that the players headed in opposite directions in each lane both make their move either to the right or left.
In the second part of the exercise, you will remove the obstacle. The balls will all be moved to the one end. The player with the ball in each lane will pass to the player at the other end and then follow their pass. The two will now play 1v1 in their lane.
Next, you can transition to 3v3. Here all of the players must stay in their lanes. A player at one end will pass the ball to one of the three players at the other end. The players will then try to score in any one of the goals at the other end. Each team is attacking three goals and defending three goals.
In the next progression, two attackers are allowed to move into the same lane. This should become easier for the attacking team to score.
Next, you can allow two defenders to also enter the same lane.
This is a great drill to get a lot of reps and work on different moves.
This is just one of many great dills and other resources available at World Class Coaching.
The YouTube video below has audio, so please make sure that your speakers are turned on. Note that some school block access to YouTube.