It's very difficult to crack this exam in 1st attempt. I have done this PMP certification exam and I was taking classes from Koenig Solutions.
According to me, Most important thing is knowledge. You have to increase your knowledge from online, read the informative article, use online tutorials, watch the video, Use forum & community websites.
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®