07. Don’t say: Can you do something that looks exactly like [this other designer’s work]?”

Why? Aside from copyright issues (and possible legal consequences), this should be a matter of ethics. No designer should be okay with copying another artist’s work outright, and you shouldn’t expect them to. Instead, try pointing out what you like about the design specifically, and ask your designer to do their own take on the style or try certain elements inspired by the work, like a color scheme, basic layout, or general aesthetic (clean, vintage, bold, etc.).