To break the concept of a ‘designer’ down quickly, let me just say that ‘designer’ and ‘communicator’ should be interchangeable synonyms.
A designer isn’t just going to make your letterhead look nice, they are going to consider who you are, who your company is, who your audience is, what will go on your letterhead, what information is most and least important to display, what the competitors in your field are doing with this medium, etc. They are going to pull apart your content and reassemble it in a way that helps you communicate to your audience in the best possible way.
Blogger and designer Alex Cue notes “Good graphic design ties a piece together. Typography, colors, images, and hierarchy are the resources a graphic designer uses to compose a design that clearly communicates information, value, and reasons to care in a quick, eye-catching manner.”
So, the major takeaway from this point is: don’t discredit design as simply an aesthetic thing. Sure, it makes your content look professional, consistent and enticing, but the reality of it goes so much deeper than that.