It’s not really as scary as it looks. You can get an idea of the common-sense approach the Chicago people take by checking out their Q&A page.

Sure, there are more user-friendly options for writers, but for the professional editor, The Chicago Manual is indispensable. I use it to jog my memory, to solve sticky problems (like how to hyphenate “early twenty-first-century French furniture”) and to help with style decisions, along with The Associated Press Stylebook and others.