Your junior and senior years are crucial for preparing your college application. During this time, you want to take tough courses, get great grades, prep for your standardized tests, choose schools to which you want to apply and demonstrate leadership in your extracurricular activities. So your first job is to manage your time well.
Start by putting key dates in your calendar at the beginning of each school year to help stay on track. (We've included some general guideposts below that will save you a lot of angst with other deadlines and appointments you'll have come up later.)