Start with a decision, not decoration
A useful certificate 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 recipients and organisations needing a clear record of recognition or completion. The working objective is to present the recipient, achievement, issuer and date with formal clarity. 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.