Do not use invidious comparisons between your views and anyone else’s.
Avoid either explicit or implicit ‘fights’ with those holding opposing views.
Maintain a tone of sweet reasonableness throughout any document.
Admit that there is some risk (where scientifically appropriate).
Use some technical terminology to make your explanations understandable, but always give brief explanations in nontechnical language (exposure, dose, likelihood, etc.).
Be bold in asserting that the only reasonable basis for understanding risks is the accumulated weight of scientific evidence, not single published studies, older studies that have been superseded by newer ones, or outlier studies. Say something like: “We strongly recommend that people do not rely on the other types of studies mentioned” [i.e., single published studies, etc.]
Be bold in recommending to the public that they exercise caution when making up their minds as to what to believe about any risk, including asking themselves what is the source of any piece of information which they have read or heard about from a friend, and whether that source is likely to have the expertise needed to make a reliable judgment on the risk in question.
Don’t hesitate to advise your audience that, if it is possible for them to do so, it is fine to seek to minimize personal risks (usually by limiting exposure) when it is relatively easy to do so and does not otherwise inadvertently create or increase another risk.
It is perfectly acceptable to advise people who are preoccupied with certain risks that alternatives they might choose almost always carry their own risks, sometimes higher ones.
Brevity is the soul of communicative effectiveness when it comes to key messages.