Effective communication is a skill. Like any skill, it can be learned and can be improved with proper practice and repetition. The key is making successful communication a habit.
Strive to get to a level 4 or 5. Talk on both ends of the floor. Encourage teammates when they make a great play as well as correct (help) teammates when they make a mistake.
When we put 5 players on the floor, we need their collective communication rating to be > 20. Maximize your ability to play as a unit.