Four
The fours are the stocks in your portfolio that are ready to be sold at current levels. These are particularly important stocks when the market turns south. "In the event of a pullback, these are stocks in which you have profits, potentially big profits. Don't give them all back; ring the register," Cramer said. These stocks are also stocks in which the fundamentals may have changed. "Again, blow it out. If you think it's going lower, even just short-term, sell some of them." These stocks can provide you with needed cash, which in turn can be deployed elsewhere in the market, in stocks that you think are just too cheap to pass up.
Three
These stocks are almost ready to be sold. "Threes are stocks that you'd like to be higher before you sell, however, they can be sacrificed if other stocks seem too cheap to pass up and you want more cash," Cramer said.
Two
These are stocks that you want to buy, but not at current prices. A selloff is a good time to visit these stocks. "I like to wait for a 5 to 10 percent pullback from the highs to pull the trigger," Cramer said.
One
These are stocks that you want to buy at current levels. "They're top flight names," said Cramer. "You've done your homework and you're confident they're good." The Mad Money host believes investors should make their moves on "ones" during a pullback, the nastier the better. Cramer says pick your entry point and then wait for the downdraft to drives these buys to your preferred level.
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Cramer says if you always rate your stocks on this scale and discipline yourself to act as outlined above, you'll not only profit but you'll navigate even the nastiest selloff with the aplomb of a pro.