British Parliamentary Debating for Beginners
The attached document is a guide written in May 2017, detailing the basics of British Parliamentary debating. It contains sections outlining how the game works, what you can expect to get out of it (spoilers: communication skills and the ability to argue really well), and the basics of how to win debates including a breakdown of analysis, rebuttal, structure, prep time, framing, the different positions on the table, how different motions work. It also contains some guidance on judging debates, as well as a little bit about why the rules are the way they are.
It's primarily aimed at novices, but schools debaters who've been speaking for a little while might also find it helpful. If you enjoy it, please feel free to share it with others!
You can find the PDF here: British Parliamentary Debating for Beginners