You may know what kind of score you’re aiming for—what the admission rates at your college of choice have been for different SAT scores. During your practice, you shouldn’t aim for this score: You should aim somewhere higher than your target. This preparation will make it more likely that you’ll be able to hit your target even if you have an “off” day, or some other disaster (mental or otherwise) crops up during the test. If you can consistently get higher scores than your goal during practice, you’re on a good track to hitting your goal on the actual test.
Also keep in mind that many students end up taking the SAT many times, so if this is your first time sitting the test try to stay cool by reminding yourself that this is just a “dress rehearsal” for the real thing if you don’t like your score now.