What should you do to fight foreign invaders who have taken over your country if actual fighting is not an option?

This is the question explored by this actual World War II manual: the idea is that an average, ordinary citizen can significantly handicap the enemy through simple acts of sabotage, with minimal fear of punishment or retribution.
Since World War II, US intelligence agencies have devised innovative ways to defeat their adversaries. In 1944, CIA’s precursor, the Office of Strategic Services (OSS), created the Simple Sabotage Field Manual.
This classified booklet described ways to sabotage the US’ World War II enemies. The OSS Director William J. Donovan recommended that the sabotage guidance be declassified and distributed to citizens of enemy states via pamphlets and targeted broadcasts.
The word "sabotage" appears in the beginning of the 19th century from the French word "sabotage". It is sometimes said that some workers (from Netherlands for some, canuts from Lyon for others, luddites in England, etc.) used to throw their "sabots" (clogs) in the machines to break them, but this is not supported by the etymology.
A book about how to sabotage Germans as they invaded France. It was interesting. Don't go blowing up railroad tracks or you'll just get killed or caught.... leave that for the experts.
As a worker you can do things like not sharpen your tools.
As a manager of a factory you can require frequent pointless meetings and demand every single point be dealt with. Does that sounds familiar? Even though this was not meant to be philosophical, it made you think about the way you do things. Are you sabotaging the work that needs to be done? Or.. Are you a valuable employee?
This was a fascinating read which provides an interesting historical perspective, and while some of the sabotage techniques would no longer be effective, many would work just as well today. I'd be interested to know how much this manual was put into practice, and how much sabotage was used against foreign occupiers in Europe during World War II.
I read this book on my Kindle, and I'd definitely recommend it. It truly is a manual--so a fairly quick read.