Hi there Hehe,
I am not the most fantastic debater; however, I do have some prior experience and achievements. For the last two years, my teams have made it to playoff rounds 3 and 2, respectively. Thus, I am qualified to offer some sort of credible advice.
If you are really invested, you could do a bit of research on the DAV website about the judging criteria or bring a couple of your teammates to attend one of their debating camps.
For prepared topics, we often would just get together, after school, on the day of the debate and spend the next 3 hours preparing. Realistically, DAV doesn't want you to spend 20 hours crafting a speech, hence the prevalence of secret topics in Grades A and B.
Obviously, there is no singular approach that will work for everyone; however, I would like to stress the importance of communication, especially with secret topics. No adjudicator wants to hear similar arguments, nor rebuttals from all 3 speakers.
One piece of feedback we often received is about the quality of our rebuttals. It is imperative that you listen to the definition of the topic, from the first affirmative speaker, because it may sometimes be unorthodox, thus you may waste time rebutting ideas that aren't exactly related to the topic. Similarly, although this may seem obvious, if the opposition raises a solid argument, try your best to rebut it, since, when left unrefuted, it may very well be the cause of your loss.
Hope this helps. If you want some more specific advice, I can try and rack my brain for something.
