(updated nov 2020)
First team member (TM1)
1) The Proposition has the burden of proof - Challenge the Proposition team with what it needs to demonstrate to win the motion and raise the bar!
2) Clash with Proposition TM1 - rebuttals (prepare for upto 2 minutes of your time)
Don't burden yourself with more than the motion requires ("better than" is less than "the best")
3) Signposts the well prepared points that Team Member 1 and TM2 will be making.
4) Delivers a structured speech of 2-3 main points selected because they have supporting (quantitative) examples - it is better to reject others to avoid a long shopping list of unconnected ideas / personal views
5) Provides a summary and brings their speech to an organised climactic close within 7 minutes

Second team member (TM2)
1) Clash with Proposition TM2 - rebuttals (prepare for upto 2 minutes of your time)
2) Signposts the different well prepared points that TM1 introduced.
4) Delivers a structured speech of 2-3 main points selected because they have supporting (quantitative) examples - it is better to reject others to avoid a long shopping list of unconnected ideas / personal views
4) Provides a summary and brings their speech to an organised climactic close within 7 minutes

Third team member (TM3 Summariser)
1) Reviews well prepared points that Team Member 1 and TM2 have made
2) Adds supporting points from the floor - but not any new unmentioned points of their own.
3) Summarise the main differences with the Proposition.
4) Brings their speech to an organised climactic close within 3 minutes

All team members have to provide rebuttals: impromptu comments to weaken or undermine your opponents claim - this is done most easily immediately after the opponent's speech at the beginning of your speech - so you don't have to prepare so much content.

Lastly, less is more - fewer arguments that are well supported are better than a shopping list of unsupported opinions.
Watch the lights and give your speech a great climax in good time. "…. and I urge you all to Oppose this motion !!!!"