Most people want the short answer, the quick fix. "Just tell me what to do and I'll do it".
They think if you give them the answer, they will know the question. But just like Carnac The Magnificent (OK kids - Google it) the answer might lead to the wrong question.
There are hundreds, probably thousands of books and articles about how to be a positive person - the power of positive thinking, etc. The steps of "How to" are easy and simple, virtually anyone can really do them. The "What to do" is a short list, nothing to it.
But before we get to the content of any discussion, it is important to set the context. The "Why" is the key. The "what's important about being a positive person, to you?" must be explored. Otherwise it is just another feel-good pamphlet sitting in that stack at the edge of your desk; another book of affirmations that you never open.
Context is set by asking probing questions, giving examples, analyzing what actually changed in people's lives and what triggered the change. Change is the one constant in life, and change is hard. It is so much easier to stay in the status quo, to accept that, maybe, life sucks a large percentage of the time.
Or maybe - when we have established the context of Positivity, the How and What will become not only easy, but will make sense and be worth pursuing.