The Essay is one of the most important parts of the SAT. Why? Because it comes first on the test.
When students are just starting to prepare for the SAT, they almost always ask about the Essay. "I've heard that most schools don't even look at the writing," they say. It is true that some colleges are not interested in the Writing Section score. You still have to do that part of the test, however, so the way you do it can have a strong effect on the way you do the entire test.
When you heard the words "You may now turn the page and begin," the first thing you will see is the Essay question. For the first 25 minutes of the nearly 4 hours you will spend on the SAT, you have no choice but to work on the Essay. Knowing that you are very well prepared will give you more confidence for the rest of the test period.