Draw an imaginary straight line from the outer sides of the ball of your nose to your brows. That is where eyebrows should start and where you should begin, especially if you're new to shaping. It's also good for wide set eyes (too far apart), because it makes eyes "appear" closer together. A large forehead also benefits because taking too much hair in between the brows makes the forehead look even bigger.
If you have close set eyes, a small forehead or this option is too much hair for you then go to the next page.