With Forex it is possible to earn money trading just one currency, the EUR/USD, as it is the currency that moves up and down the most because it is the most popular pair.
Trading just this one currency is a smart Forex move because the trader learns how to specialize himself in reading technicals about that one currency and also reading and interpreting currency news for the EUR and the USD.
Another advantage is that the trader is always glued to the EUR/USD M1 screen and always looking for the latest trading opportunities. This puts him in a far superior level from the beginners that trade random most of the times and base their trades on good luck, God's good humor, etc.
At this moment, the EUR/USD just dropped 70 pips. Is this the right moment to buy or sell? Well, in one hand we have the technical analysis saying this is the perfect moment to buy but if on the other hand the newspapers publish horrible news about Europe, Germany or France or Greece, the EUR will continue to move down sharply.
Finally there is more information regarding the EUR/USD than any other currency pair so do not let information overload to become an obstacle in your way to the profits.