Choose a point of view to discuss autism from. Ways to look at autism include: definition, social, psychological or parental, among others. For instance, discussing autism from a parental view is an appeal to emotion, which is a strong persuasive tool.
Consider the audience of the essay. Are they undecided, on your side, or against you? If they're undecided, persuade them to your side by paralleling opposing arguments. If they are on your side already, your essay should have their faith reaffirmed. And if they have opposing views, acknowledge their argument and write with understanding.
Determine talking points in relation to your audience and pick your evidence wisely. For instance, if you are writing to persuade parents of the dangers of vaccinations, you could cite other parents with legitimate claims and provide evidence of autism linked to vaccines.
Identify which opposing view is the most threatening and seek to take it down through explanation and refutation. When discussing opposite sides, always try to understand, even concede, rather than outright dismiss. For instance, "It is true that autism may be considered an educational problem, but a decade of autism research has shown autism to be an entire system disorder."
Outline the essay with each main point and sub-points to discuss within the body paragraphs. For example: the first body paragraph discusses the MMR Vaccination by deliberating a scientific connection between autism and the MMR vaccination, if there is one, and the risks or benefits of refusing an MMR.
Draft the introduction. Begin the introduction with a strong statement, quotation, anecdote, statistic, question or an exaggeration, such as: "Lisa Ann's child was diagnosed with autism shortly after receiving the MMR vaccination. Some see a case with not enough evidence. Others see a parent with living proof."
State the thesis (intention or purpose of your essay) clearly. For example, "Parents of autistic children face discrimination from insurance companies, schools and society." This thesis tells the audience exactly what the essay will discuss -- discrimination from different venues.
Draft the body paragraphs according to your outline. Each body paragraph should address your major points with evidence and examples that support your claims. Leave at least one paragraph to explain a significant opposing view and refute it with examples and logic.
Draft the conclusion. Restate the thesis of the essay and relate back to the introduction. End the essay with a memorable remark such as a powerful statement, quote or fact that prompts the reader to take action. For instance, "if this discrimination in our school system is left untouched, the families of autistic children will continue to suffer for many generations."