I have read that a good title (& subtitle )for a non-fiction work should be one that (a) tells what the book is about in a catchy manner, but also (b) would would contain keywords that someone would look for on an Internet search. I don't really know how to begin, so I will put down what my book is about, and wait for suggestions. Briefly, it consists of explanations for the lay person to clear up commonly held misconceptions about wide-spread terms and concepts from science.
Thanks, SethLoki! Good suggestion! My delayed response comes from the fact that the forum did not notify me as it was supposed to when I got an answer.
@agasfer The question to ask yourself is what is the style of the book? Is it humorous, is it dry?, what age group and which demographic is your target audience etc. Below are a few ideas I have come up with. I went with the humorous style and are twists of existing popular fiction books (can you guess which ones???) To the end of the universe and back again A layman tale A layman's guide to the galaxy science The answer is 42 Answers to ultimate questions in Science
The Annotated Guide To Commonly Held Misconceptions About Wide-Spread Terms And Concepts From Science