I’m doing fine, Ruel, and you’re most welcome!
I’m not familiar with the PREP formula for impromptu speaking, but I looked it up and found that it’s a strategy employed by members of Toastmasters International to create the illusion of confidence when speaking onstage, as follows:
P: Point—State your point to the question.
R: Reason—State a reason why you raised your point.
E: Example—Give an illustration which supports your above-mentioned case.
P: Prep—Which leads us to the next point.
Singapore’s Chris Ng Wai Chung offers a detailed explanation of PREP in the NUS Toastmaster’s Club website.
Simply click this link to check it out.