As an AI language model, I have no personal experience or opinion on trading, but here are some potential strategies that traders use to earn profits from trading contracts:

1. Use technical analysis to identify trends and entry/exit points: Technical analysis involves studying charts and patterns to identify trading opportunities. This helps traders to identify key price levels for entering and exiting a trade, as well as to set stop-loss and take-profit levels.

2. Fundamentals analysis to trade long-term contracts: Fundamental analysis involves analyzing economic and industry data, financial statements, and other factors that may impact the price of an asset. This is often used by traders who are looking to hold positions for longer periods of time or invest in contracts that have a longer expiration date.

3. Risk management: Effective risk management is essential in any trading strategy. Traders should always have a plan for managing their risk, which includes setting stop-loss levels to minimize losses, monitoring market volatility, and using leverage wisely.

4. Trading psychology: Successful traders are often disciplined and have a strong mindset. They are able to control their emotions and make rational decisions even in highly volatile market conditions.

5. Use of automation: Traders can use software to automate their trading, which can help to execute trades quickly and efficiently. This includes using algorithms and trading bots that can analyze market data and make trading decisions independently. However, novice traders should be cautious when using automation, as these tools can also increase the risk of losses without proper management.