To prepare means to get ready for something. When you prepare for a test, you'll get a better score than if you don’t.
Look at all the variations that you find with prepare. If you prepare yourself mentally for an experience, you sent you mind on it happening. If you're going to tell your family that you're moving out, you might want to prepare them by having them sit down. Are you prepared for their reaction? Are you prepared to defend your decision? You can prepare wood to be painted by cleaning and sanding it. And if you prepare dinner, you cook it.