The first thing to do when shopping for a car is to decide to have fun. There are probably a couple of cars that you are already interested in. Read everything you can about them. Find out all of the features that they have available. I suggest that you read auto reviews from at least three sources on each car.
Different reviewers take a different viewpoint on the same car.
Microsoft's Carpoint offers two reviews on many cars. Edmund's site offer a brief synopsis of every car available. CarHunter from the San Jose Mercury News is another valuable resource. Many reviews, including those at Edmund's, list the cars which are competing with the one that you are reading about. I encourage you to look at those cars as well as any others which you think you may have even the slightest interest in.