The 'Custom Tactics' and 'Player Instructions' menus are powerful tools to tailor your team's behavior. Don't just stick to default settings. Experiment with different defensive styles (e.g., Press After Possession Loss, Drop Back) and offensive styles (e.g., Fast Build Up, Long Ball).
Individual player instructions can dictate specific runs (e.g., Get In Behind for strikers), defensive positioning (e.g., Stay Back While Attacking for fullbacks), and creative freedom (e.g., Free Roam for CAMs). Having multiple custom tactics saved allows you to switch between them mid-game to adapt to your opponent's strategy.