Hi erinbee,
Your GMAT Score out of 800 is based on just 2 things: your Quant Scaled Score and Verbal Scaled Score. The IR Score and AWA Score are completely separate numbers (out of 8 and 6, respectively) and have no impact on your Score out of 800. While you will receive an Unofficial Score Report on the day of your Exam, those results are almost always the same on your Official Score Report (in some rare circumstances, I've heard of an Official Score varying by 10 points - for example, 600 to 610 - but again, that is remarkably unlikely to occur).
Since it sounds like you're just beginning your studies, then it would be a good idea to take a FULL-LENGTH practice CAT Test; you can take 2 for free at
www.mba.com (and they come with some additional practice materials). If you want to do a little studying first, so that you can familiarize yourself with the basic content and question types, then that's okay - but you shouldn't wait too long to take that initial CAT. That score will give us a good sense of your natural strengths and weaknesses and will help provide a basis for comparison as you continue to study. A FULL CAT takes about 3.5 hours to complete, so make sure that you've set aside enough time to take it in one sitting. Once you have those scores, you should report back here and we can come up with a study plan.
I'd like to know a bit more about your timeline and goals:
1) What is your goal score?
2) When are you planning to take the GMAT?
3) When are you planning to apply to Business School?
GMAT assassins aren't born, they're made,
Rich