preparatory
Done beforehand to get ready for something important.
Preparatory means designed to prepare you for something important that comes next. A preparatory school (often called a “prep school”) is a school that prepares students for college by giving them rigorous academics and study skills. Preparatory work is the practice, research, or planning you do before the main event.
Think of preparatory activities as your warm-up before the big game. A musician does preparatory exercises before a concert, running through scales and difficult passages. A scientist conducts preparatory research before launching a major experiment. You might do preparatory reading before a field trip to understand what you'll see.
When something is preparatory, it's all about getting ready for what's ahead. A preparatory meeting happens before the actual decision is made. Preparatory sketches come before the final painting.
Preparatory work is purposeful practice or planning that makes the real thing go better. The chef's preparatory work (chopping vegetables, measuring ingredients) means dinner comes together smoothly. Your preparatory studying means you walk into the test feeling confident rather than panicked.