Recently, I’ve been looking at trading volume data in the foreign exchange market and discovered that the world's most active financial product isn't stocks or bonds, but forex. Especially in recent years, even mainstream currencies in mature markets have experienced quite large fluctuations. Plus, foreign currencies can be used both for investment and daily transactions, so the participation barrier is actually lower than other products.

Speaking of forex investing, it all comes down to one word—profit from the exchange rate difference. What is an exchange rate difference? Simply put, it’s the price discrepancy of the same currency at different times or through different channels. Traders profit by predicting exchange rate trends, buying low and selling high or selling high and buying low. For example, if you expect the euro to appreciate, you buy 100k units of EUR/USD at 1.0800, then close the position when it rises to 1.0900, making a profit of (1.0900 - 1.0800) × 100,000 = $1,000. It sounds simple, but behind it requires a real understanding of the market.

To profit from exchange rate differences, there are mainly a few methods. The safest is bank foreign currency fixed deposits, which carry the lowest risk but also limited returns—mainly earning interest rather than exchange rate differences. A medium-risk option is foreign currency funds, which allow participation in exchange rate fluctuations and profit from the appreciation of the underlying assets. For example, if you believe the yen will appreciate and also think Japanese stocks are undervalued, you can buy yen-denominated Japanese stock funds, benefiting from both directions.

Those truly aiming to turn a profit from exchange rate differences need to use forex margin trading. This is a high-risk, high-reward approach that amplifies gains through leverage. The forex market typically offers leverage from dozens to hundreds of times, so small movements can generate significant profits. For example, if the yen suddenly surges from 161 yen per dollar to 141 yen per dollar, using leverage can multiply your returns many times. Plus, trading costs are much lower than banks—banks usually have spreads over 0.3%, while legitimate trading platforms might have spreads as low as a tenth of a basis point.

Regarding techniques for making money from yen exchange rate differences, I’ve summarized several practical methods. Range trading suits situations where prices fluctuate within a certain band, requiring identifying support and resistance levels for repeated trades. But once the range is broken, stop-loss immediately; otherwise, losses can be severe. Trend trading involves capturing the main market direction and holding medium to long-term. For example, during the dollar’s appreciation in 2021, as long as you judged the trend correctly, returns were relatively stable.

Day trading is suitable for those who prefer short-term positions. The focus is on monitoring central bank policies and economic data releases. For instance, when the Federal Reserve announces a rate hike, the exchange rate can fluctuate wildly. If you react quickly, you can profit within 1-2 days. Swing trading falls between day trading and trend trading, combining technical and fundamental analysis to identify key signals like breakouts and trend reversals. Position trading is a long-term holding strategy, suitable for those who don’t want frequent operations, with the key being to find low-cost entry points.

Why choose forex? First, its uses are broad—travel abroad, overseas shopping, trade transactions—all involve currency exchange. Learning to profit from yen or other currency differences can both arbitrage and hedge risks. Second, trends are relatively clear—by understanding the interest rate policies and monetary policies of two countries, you can roughly predict the direction of the exchange rate. Third, liquidity is the highest—over $6 trillion traded daily worldwide, with high market transparency and low manipulation risk.

In terms of trading hours, banks generally operate from 9 a.m. to 3:30 p.m., closed on weekends and holidays. But forex margin trading doesn’t have a unified exchange; it’s divided into four sessions—London, Sydney, Tokyo, and New York. Due to overlaps, trading can basically run 24 hours from Monday to Friday without interruption.

Honestly, there’s no absolutely best method for forex investing. It depends on your risk tolerance, capital size, and trading habits. Preparing thoroughly is key—deep market research will help you find suitable profit opportunities. If you’re not ready to put real money in yet, practicing with a demo account to hone your skills is a good idea before jumping in.