I've been an OmniFocus user for about five years now. I started back on OmniFocus 1.0! Over that time I've written a book about it, developed a step-by-step video course for it, and now I'm distilling everything I've learned in those five years into this course.
OmniFocus can be daunting and overwhelming. But with a little planning, some examples of how others use it, and the summarization of what works and what doesn't, you can get your system flowing smoothly and simply.
This is not a one-size fits all system. This about finding the system that works for you.