When you are writing a message you want your recipients to believe, you should use cognitive ease to work in your favor. Cognitive ease refers to when your mind is relaxed and not putting in much effort, instead of stressed, strained, or worried. You want your audience to be in a state of cognitive ease when reading your message, because they will be less likely to question or disagree with what you are saying.
Print your message in bright blue or red bold text.
This will catch your reader's attention.
Do not use complex language if you can avoid it.
Using pretentious and bombastic language is generally considered a reflection of low credibility.
Write your message in rhyming verse.
Your message will stick in people’s minds longer.
If you are quoting sources, try to pick those with easily pronounceable names.
Otherwise, your audience’s minds will have to put in effort to process it, and they will shift out of a state of cognitive ease.