I always hated outlining in school. My outlines never survived the first draft and they felt unnatural to me. If the traditional outline doesn’t work for you, try some alternatives, like starting with stories.
Spend some time dredging your mind for stories about the subject of your book. Use short descriptions to describe them. Include other story-like devices, such as jokes and quotes, that you’ve used to explain your subject to others.
Then, decide which are your most important stories and make each one the centerpiece of a chapter. Add statistics, studies, and other examples to support them.
Every one of us is a unique writer. You’ll do best if you try different ways of working until you settle on one that’s right for you.