1. Never slap a man who’s chewing tobacco.
2. Never kick a cow chip on a hot day.
3. Never miss a good chance to shut up.
4. Always drink upstream from the herd.
5. If you find yourself in a hole, stop digging.
6. The quickest way to double your money is to fold it and put it back in your pocket.
7. There are three kinds of men:
Those who learn by reading.
Those who learn by observation.
And those who have to urinate on the electric fence and learn by experience.
8. Good judgment comes from experience, and a lot of that comes from bad judgment.
9. If you’re riding ahead of the herd, take a look back every now and then to make sure it’s still there.
10. Letting the cat out of the bag is a whole lot easier than putting it back in.
11. After eating an entire bull, the mountain lion felt so good he started roaring. He kept it up until a hunter came along and shot him. The moral of this story: when you’re full of bull, keep your mouth shut.
And
12. (From my wife): When the horse is dead, dismount. (For people who keep advocating ideas long after everyone has lost all interest.)
Biscuit City 
My sister has a similar #12: "Put down the stick. The horse is dead." But I quote the first rule of holes (#5) all the time…
I like them both! Thanks!