(updated Oct 2018)
First team member (TM1)
1) Sets the scene, explains the problem and states why the motion is the solution.
2) Defines the terms of the motion.
a) If there is more than one available definition, keep it as straight forward as you can.
b) Don't burden yourself with more than the motion requires eg: "is a better solution for" is less than "is the best solution for",
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 Opposition TM1 - rebuttals (prepare for upto 2 minutes of your time)
2) Signposts the different well prepared points that TM1 introduced.
3) 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)
1) Identify the main issue that divides the two teams that voters should consider.
2) Explain why the Opposition's view is wrong.
3) Reviews the 1 or 2 most important points that supports your argument.
4) Brings their speech to an organised climactic close within 3 minutes

If you provide some quotes and supporting details - it is likely that you will use some notes.

Defining the Motion
For example if the motion is "xxxx xxxx xxxxx xxxxxx" is not that onerous,
what TM1 has to do is define the words of the motion (meaning of onerous),
and set the Practical limits (only in the UK),
and limit the consequences of the motion.

There will be benefits …. "but we won't be closing prison / hospital / xxxx down" …

The team has to decide what the rational limits are … the opposition will do it's best to challenge this.

TM2 and TM3 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.

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 Support this motion !!!!"