As an academic writer first and foremost, I have encountered several pieces of advice for how best to make my writing accessible to the layperson. Some tips are obvious, such as not using jargon. However, the best piece of advice was presented to me by a Professor on my undergraduate course, a recommendation I use not only in my non-academic writing, but also in my scientific communications: Keep it simple!
Writers all too often wish to show off their intelligence by using complex language and assuming a certain amount of knowledge from their readers. They think that by ‘impressing’ their reader in such a way, they will appear as superior intellects. However, all this does is alienate their audience.
The trick with non-fiction writing is not to make YOU appear intelligent, but to make the reader feel that THEY are intelligent. By explaining complicated matters in a simple, easy to read manner, the reader will grasp the concept and come away from the experience feeling better about themselves and you as a writer. I experience this all the time when reading certain popular science books on Quantum Physics. Pick up any book by Brian Greene, or Michio Kaku, and they will make you feel like you are an expert in the impossible. Richard Dawkins is also another excellent proponent of this method. They don’t shy away from using simpler language and concepts to portray their message.
A lot of writers when presented with this advice do not wish to ‘dumb-down’ their writing; they still cling to their desire to use complex language and terminology, as they fear that not doing so will make them look like incompetent writers. They feel that they have to use long, rarely encountered words in order to demonstrate how educated and eloquent they are as writers; all they accomplish, however, is to annoy the reader, bored with constantly reaching for the dictionary.
So, whether you are writing fiction or non-fiction, keep it simple! Your reader will thank you.