Make a file for printed materials that you like. Bookmark websites that appeal to you.
Here are some criteria to consider: colors, tone, writing, message, cleverness, uniqueness, attention getting, challenging the customer to not read at their own risk, and other criteria that are important to you.
This will fuel the creative process for both you and your writer/designer. And it will save money down the road on the design process. A graphic / web designer likes to know your taste so they have a good starting point on producing material you’d like. And that ultimately save you design time, which saves you money.