Against a team pressing with three forwards, your back three is matched one against one. That's where the keeper comes in: they're the spare player. A 3-3-2 then uses its central midfielder as the hinge and its wide midfielders to go forward, with the two strikers giving short and long options.
Step 1 of 5
They press our goal kick with a front three. The keeper is our spare player.
Use the keeper as the extra player so it's four against three, and play through the gaps between their forwards into midfield.
Is a 3-3-2 good for young teams?
Yes. It's balanced, gives two strikers to aim for, and the shape is easy to understand.
What if we keep losing the ball when we play out?
Expect it at first. Keep the shape, practise the same patterns in training under light pressure, and judge the decision rather than the result. If a game is getting away from you, it's fine to mix in a longer pass to the striker for a spell.