1. Never take a laxative just before the market opens. 2. Never take Viagra just before the market opens. 3. Never take Viagra and a laxative together. You won't know if you're coming or going.
Never say KISS ("Keep it simple, stupid.") The simplest strategy is buy&hold. Good luck getting that to work once the bull goes away. The trader who wins is the one whose strategy falls into the sweet spot between overly complicated and overly simplified.
Never trade until you have found your edge The rest are just add on. If you have edge, you will always able to come back in profit stage regardless what happen in short term, e.g. You take some loss due to not following rule, fat fingers, black Swan, market manipulated by fed/banks, trade when you drunk or in emotional and etc. If you don't have edge, all the best rules or all the things "a trader should not do" will not help.
Err no D08 is right, you can trade perfectly and random chance will put you negative, even the most moronic trading ideas have positive days eventually.