The School I go to has a really good CFI program so I followed that. But basically I made lessons for every task in the PTS ( for the bullet points I used right from the PTS bullet points that they want to hear). I started with the FOI then Regs then into Technical areas, and finally maneuvers to go along with the flying practice. During all that time while prepping lesson plans, we presents our lessons and taught them to each other in the group to develop the presentation skill. Other than that I studied the oral book, Made sure I could answer every FOI question in the PTS from memory, then just kept practicing teaching lesson plans and talking in the airplane. Also made sure all my resources where labeled and organized so i could quickly reference them. When it was all said and done, I was VERY prepared for the oral. But good luck to you, it was an enjoyable experience for me for the most part. you'll do fine.