A. First submit application through PMI web site. You should make small notes about how you are going to meet the requirements.
List the following
1. Details of 35 contact hours of formal education. When you got them and where?
2. List of the projects you are going to fill in the application. Make notes of start date, end date, name of the project, supervisor, deliverables, time spent on different phases of the project.
Once you have prepared a rough details then got to http://www.pmi.org/Certification.aspx and register your self and it will guide you through the application process. You have 90 days to complete the application once you started it.
B. After you submitted the application it will take about 5 days for review. Once you are approved you will get email notification. Now you can pay for the exam. Currently computer based exam fee is $405 for PMI members and $555 for non members. I think it is worth to become member of PMI which is about $129. ( In case you get audited you will get notification and then you have to provide documentation to support your eligibility.)
C. Once you are approved and you have paid for the exam, then you will get notification to schedule the exam. You cannot schedule the exam before this. Once you are approved to schedule the exam you will have one year to take exam and you can have 3 attempts. You schedule your exam in such a way that you have enough time for preparation.
D. Now start preparing for the exam.
Good Luck
Further reading