Want to earn a lifetime of coins, rather than spend a lifetime struggling in the crypto sea—this is the most important principle that crypto enthusiasts should understand.

Let's directly discuss the three most reliable rules for contract trading. Mastering and executing them well can save you at least three years of detours.

**First Iron Law: Lock in profits once gained, protect your bottom line before making moves.** Once a coin rises more than 10%, sell if it falls back to the purchase price; when earning 20%, set a firm stop-loss to at least preserve half of the profit before considering action; at 30% profit, keep a 15% stop-loss. What's the benefit of this approach? Even if you can't pinpoint the exact top, you can steadily pocket profits. Don't be greedy—repeatedly bouncing in and out of the market just to get shaken out, and in the end, your gains might not even cover the transaction fees.

**Second Iron Law: Cut losses quickly, don't drag things out.** If losses reach 15% (this percentage can be adjusted), cut your position immediately—this is timely stop-loss. Many people are reluctant to cut losses, resulting in small losses turning into huge ones—that's a real tragedy. Before opening a position, always plan your stop-loss point. If you don't have this habit, stay away from contracts altogether. Don't regret it if the price rises later—it's a sign you entered at the wrong point. Mistakes come with a price; that's how you pay tuition.

**Third Iron Law: If you sell and the price drops, buy back in.** If you sold coins and later see the price fall but still believe in them, buy the same amount back. Although you'll pay more in fees, this helps avoid the big pitfall of missing out on gains. When the price returns to your sell point, buy back unconditionally. For coins that jump around wildly, change your entry point and don't stubbornly hold on.

In summary: short-term trading is about principles and discipline. Quick in and out isn't reckless; taking profits when the time is right isn't cowardly. Consistently earning steadily is always more reliable than greed. In the crypto world, blindly rushing in will eventually lead to pitfalls. Finding a reliable strategy and following through is the way to survive longer.