It’s a common fact that there are millions of people out there who couldn’t find their own arse with both hands. Or, in this particular instance, their own knob.
For the majority of the human race, finding out things is quite easy. We either use that well proven method of trial and error, driven on by our inquisitiveness and imagination, or we use Google.
For the rest, there is a book written for Dummies.
If you didn’t grow up in an English boarding school, or were perhaps too preoccupied as a teenager by watching SciFi to find time to have a group synchronised hand-shandy along with your mates in the woods, then this book is possibly just what you have been searching for.