Since I did not have much experience with AWS, I took both Linux Academy and the Architecting on AWS. The level of details that is provided in Linux class makes a big difference in my ability to pass the exam. Helpful hints: Do all the labs. Get the hands-on experience. Aside from knowing S3, EC2, EBS, ELB, Route 53, Glacier, RRS, RDS, DynamoDB (in essence, learn about all the services covered in the Linux course, make sure you know how SQS and SWF are used. Also, listen to the Linux instructor when he tells you to know what is defined where when setting up auto scaling. I also read the FAQs.
During the test, make sure you go through all the questions. Marked the ones you are not sure about for further review (at the end), but don't leave any questions unanswered since you are not penalized for incorrect answer.
I hope this helps.
Best of luck!