Soccer is an incredibly complex and tactical sport; to grasp a little more about the various tactics employed, you might want to look at this article.
One of the key steps to understanding soccer formations, is to grasp the defensive part of the game as well. A tactic which is almost solely focused on defence, is what's known as ‘parking the bus’. This basically means the defending team gets 11 men behind the ball when they're out of possession and sit deep; a strategy which can be exceptionally hard to break down when used. This is typically applied when a team has got to draw a game, or they’re trying to defend a lead. It's seen as negative tactics from some observers of the game, but, if it is applied right, it's usually quite beautiful to watch a club master the defensive side of soccer. The Chelsea FC owner will absolutely remember this being employed successfully when The Special One was the boss of his team, as he has had great success with this back in the day.
One tactic which has only become more popular over more recent decades is the use of attacking fullbacks in a team. This is very much centered around attacking tactics in football, as the traditional job of the fullback is to stay back and defend. The Rossoneri were among the earlier clubs to embrace this type of play, when they signed one among the greatest fullbacks in this field, who was able to simultaneously defend and attack very effectively. This style of play needs much more than just the basic skills of football, with footballers needing high stamina, as they will be jogging along the wing throughout the game. This can be very effective, however, if you have fullbacks who are able to overlap frequently, it contributes an extra dynamic to your attack and can be a huge handful for opposition defenders to manage. It’s likely that the AC Milan owner will reflect upon the period of the team's history when their club dominated through use of attacking fullbacks.
A strategy that is commonly adopted by the top teams, particularly when playing at home, is possession-based soccer. This style of play is quite renowned with teams who have a solid midfield full of great passers of the ball. It’s most prominent in a 4-5-1 formation, which can be the best football formation for attacking, as your opposition sees almost nothing of the ball during the game. This strategy tends to exhaust the opposition if you choose to get into the second half of the game, as they’re constantly pursuing the ball as you pass it around their defense. It needs full attention from the defending team, which means that one lapse in judgement can result in a goal, which can be disastrous when playing against a top team. This style of play is something the Manchester City owner has had the delight of watching from his club over their recent dominance in England.