From the SAME AS IT EVER WAS file: Bernard Baruch, a colleague and friend of Jesse Livermore’s, who made a fortune shorting the 1929 crash, and then who later advised presidents Woodrow Wilson and Franklin D. Roosevelt on economic matters, listed the following investment rules in his autobiography published in 1958 entitled Baruch: My Own Story.  These rules are still as applicable today.

1.  Don’t speculate unless you can make it a full-time job.
2.  Beware of barbers, beauticians, waiters–of anyone–bringing gifts of “inside” information or “tips.”
3.  Before you buy a security, find out everything you can about the company, its management and competitors, its earnings and possibilities for growth.
4.  Don’t try to buy at the bottom and sell at the top.  This can’t be done–except by liars.
5.  Learn how to take your losses quickly and cleanly.  Don’t expect to be right all the time.  If you have made a mistake, cut your losses as quickly as possible.
6.  Don’t buy too many different securities.  Better have only a few investments which can be watched.
7.  Make a periodic reappraisal of all your investments to see whether changing developments have altered their prospects.
8.  Study your tax position to know when you can sell to greatest advantage.
9.  Always keep a good part of your capital in a cash reserve.  Never invest all your funds.
10.  Don’t try to be a jack of all investments.  Stick to the field you know best.