Lets divide it into 5 phases:
1. Step 1
2. Step 2- Clinical Knowledge
3. Step 2- Clinical Skills Examination
4. Step 3
5. Interview Application & Matching.
You will be ECFMG Certified after you pass Step 2 Clinical Skills examination. And you cannot take step 3 exam without passing CS exam. You can take Step 3 during your residency itself. But you need to pass step 3 before the match day if you wish to get H1 VISA for the residency. And many hospitals adjudge you on the basis of completion of all the steps as it would be easy for them to proceed ahead. But that doesnt mean you have to things in hurry. Its better to do it timely next year than to do it untimely this year. So take time with study materials too. Every year competition is increasing, and for International Medical Graduates, the most important thing to prove your presence is the score, because the attending doctors havent seen your hospital and dont know about them at all. And making your application attractive is also a secret to being successful. We would try to help you out with whatever support and suggestions we can come up with.