If you're reading this, you're probably well at ease with your mouse by now. Some of us got the idea fairly easily, while others had to struggle. One of the roots of failure, I've observed, is that beginners often hold the mouse from above, like a cat that's just pounced on it and is determined that it isn't going to get away from them. Then they punch the button ferociously, and the mouse sheers wildly off target in terror.
I've persuaded several such people to relax their death-grip; to let their hand lie on the surface behind the mouse, just guiding it quietly with thumb and little finger, and gently clicking the buttons when necessary. And if their hand-eye co-ordination was shakey, then to work in L-shapes (e.g. down then across), and allow direct movement to creep in in its own time. These people have all come back a week later, pleased to report that they've got much better.
But in earlier days of computer mice, when they were still alien objects to many people, it was not uncommon for me to watch students put a mouse on its back and twiddle the mouse ball with their finger tips. The screen behaviour was wonderfully erratic, and as a method of selection it had distinct problems with clicking buttons, too.
On one occasion I watched two girls doing this and in friendly fashion showed them the proper way of using a mouse. They smiled, said thank you, and a few minutes later the mouse was on its back again. Not foolish - just their way of working. Or maybe I was seeing the birth of the trackerball...
[If you have a story about something foolish or ingenious you did to your computer, send it to firstname.lastname@example.org-Iron.]