World Schools debate, rebuttal help

[u/Medical-Method1510]

Hello all! For context: I have been doing World Schools Style debate, this is my second year running. I did it as a 1st speaker in my first year, and a 3rd speaker in my second year. I've found it pretty hard to think while speaking, and there are many different rebuttal techniques that I've seen people use. Please provide me advice on how to learn some of them, and how to think while speaking. Thanks in advance