Start with a decision, not decoration
A useful coupon sheet brief names the reader, the decision or action the page should support, and the evidence required before design begins. For this project the audience is customers choosing and redeeming one or more time-limited offers. The working objective is to make each offer, condition, expiry and redemption action unambiguous. Write those two statements at the top of the brief and test every proposed section against them. Material that does not help the reader understand, trust or act should be removed, shortened or placed in a secondary channel.