I cleared my Salesforce Admin certification(WI16) last week and here are few tips from my side to prepare for the exam:

1. I used salesforce-qa document, which I got it when I googled to find out the study materials for the exam and it covers the topics given in the study guide (except SalesforceA and Salesforce1, interestingly I didn’t get any questions from those topics).
2. Then, I started going through the questions given in the site from Part 1-Part 10 and there are about 1000 questions. I didn’t get majority of these questions on my exam though from these dumps, it has helped me to understand the nature of questions that can be asked for the exam. I have got around 20 questions from these dumps.
3. After finishing the exam, I found out this Admin-201-Certified-Administrator-notes which is gud too.

Here is the study guide and let me know if you have any questions about the exam.

P.S: Recently, I have gone through this post http://www.merivisblog.com/study-salesforce-admin-exam/ and thought of sharing it, as it could be useful to pass the exam.

There is a nice article by Ben on how to pass your Salesforce certification and here is the link