This one is easier said than done but can work well if your Mac, iPhone, or iPad is having troubles not quickly solved. Joe Caiati was an Apple Genius and gives good advice for Mac users.
No one likes visiting the Genius Bar.
If you are going there it’s because something is wrong with your Apple product and depending on the time of day, you could be waiting for a while to see a Genius. Some wait all of that time just to ask a simple question, but others may need a repair and can be without their Mac for a couple of days or more.
The list is useful but probably not aimed at the average Mac user who does not understand Plist files and whose eyes glaze over when opening Activity Monitor.