I think it takes me a minimum of 3 days to create a course syllabus, and that's for courses that I've taught before. I hadn't counted on, or I didn't realize how little I knew about teaching and course design when I started out. Each syllabus represents my latest thinking and learning on the course, the newest teaching and learning techniques I'm including and my reflection how the class "went" the last time I taught it. I'm also trying to close the latest loophole that clever students found the last class.
There are certain sections I've learned that are standard to every syllabus, and I can template: When to add/drop, the student handbook, my contact information, my anti-plagiarism section, the required textbook section.
I lack the discipline, most of the time, to focus on just one area, and will then start changing page numbers for readings, the points for assignments, twiddle with bullets and indents, instead of sticking to one topic area.
This year, for my class on critical thinking, I went analog first. I wrote out what I thought we could accomplish, what readings, and what exercises would be done, etc. on paper first, and then I typed it in. I'm more focused when I start with paper, I've learned. I'll be interested to see if I can remain focused when I take notes on my iPad.