During the 15th century, the Medici family were required to open banks at foreign locations in order to exchange currencies to act on behalf of textile merchants.[10][11] To facilitate trade, the bank created the nostro (from Italian, this translates to "ours") account book which contained two columned entries showing amounts of foreign and local currencies; information pertaining to the keeping of an account with a foreign bank.[12][13][14][15] During the 17th (or 18th) century, Amsterdam maintained an active Forex market.[16] In 1704, foreign exchange took place between agents acting in the interests of the Kingdom of England and the County of Holland.[17]
Traders who understand indicators such as Bollinger bands or MACD will be more than capable of setting up their own alerts. But for the time poor, a paid service might prove fruitful. You would of course, need enough time to actually place the trades, and you need to be confident in the supplier. It is unlikely that someone with a profitable signal strategy is willing to share it cheaply (or at all). Beware of any promises that seem too good to be true.
Trading psychology is by far, the most overlooked aspect of profitable trading.  To say it another way, you can use many strategies to turn a consistent profit, but you cannot trade profitably if you have yet to master the emotional side of trading. There is no exception to that rule. You cannot turn a profit while revenge trading. You cannot turn a profit if you’re over-leveraging and doubling down to

^ The total sum is 200% because each currency trade always involves a currency pair; one currency is sold (e.g. US$) and another bought (€). Therefore each trade is counted twice, once under the sold currency ($) and once under the bought currency (€). The percentages above are the percent of trades involving that currency regardless of whether it is bought or sold, e.g. the U.S. Dollar is bought or sold in 88% of all trades, whereas the Euro is bought or sold 32% of the time.
The possibility of losing your investment is high, so it is advisable to only use risk capital (money that you can afford to lose) when engaging in Forex trading. The Forex market offers high levels of leverage to traders. Leverage has both the possibility of high returns and high losses, and should only be used with discretion. Be disciplined and don't be tempted to overtrade.
Risk/reward signifies how much capital is being risked to attain a certain profit. If a trader loses 10 pips on losing trades but makes 15 on winning trades, she is making more on the winners than she's losing on losers. This means that even if the trader only wins 50% of her trades, she will be profitable. Therefore, making more on winning trades is also a strategic component for which many forex day traders strive.
Similarly, if you wanted to purchase 3,000 USD with Euros, that would cost 2,570 EUR. With a leverage rate of 1:30, however, you could access 3,000 USD worth of the EUR/USD currency pair as a CFD with just 100 USD. The best part, however, is that the size of the potential profit a trader could make is the same as if they had invested in the asset outright. The risk here is that potential losses are magnified to the same extent as potential profits.
One unique aspect of this international market is that there is no central marketplace for foreign exchange. Rather, currency trading is conducted electronically over-the-counter (OTC), which means that all transactions occur via computer networks between traders around the world, rather than on one centralized exchange. The market is open 24 hours a day, five and a half days a week, and currencies are traded worldwide in the major financial centers of London, New York, Tokyo, Zurich, Frankfurt, Hong Kong, Singapore, Paris and Sydney—across almost every time zone. This means that when the trading day in the U.S. ends, the forex market begins anew in Tokyo and Hong Kong. As such, the forex market can be extremely active any time of the day, with price quotes changing constantly.