You should develop an overall theme for your case. Your overall theme should be a bottom-line message stating why you should win your argument in a single sentence.
“You ought to be able to put your bottom-line message on the inside of a matchbook.”
- Dwight D. Eisenhower
My overall theme is usually a literal statement of what the case is about, but in the book Winning at Public Speaking, Shane Read uses the following metaphor as an example of a bottom-line message: “The defendant promised gold, but delivered mold.” This might not be a bad theme for a breach of warranty case.