I usually read instruction manuals for video games and detailed construction stuff like building grills, swing sets, etc... but for stuff that involves common knowledge, I don't.
My dad never reads instruction manuals. That's why he always ends up being the last to know. I beat him at every video game. He says it's cuz I'm skilled. I say it's cuz I read the instruction manual. One time, he was struggling with cleaning up some gunk. He was using Goo Gone. I told him to just rub it lightly so that all the gunk is exposed to Goo Gone, then wait a few seconds before rubbing harder to have it come off. It worked perfectly. He said, "Wow... where you learn that trick?" My response? "I read the instruction manual." 
