This really depends on how you intend to trade, whether you use leverage and to what level and how much capital you decide to risk. You could start by investing $50, or $50,000 – the sky is the limit. However, you should remember that increasing the amount of leverage also increases the level of risk you’re exposed to. Ultimately, trading boils down to a trader’s psychological tolerance and management of risk. Skilled traders are able to minimise risk and maximise profit through careful market analysis, developing an effective trading strategy and money management rules.
International parity conditions: Relative purchasing power parity, interest rate parity, Domestic Fisher effect, International Fisher effect. Though to some extent the above theories provide logical explanation for the fluctuations in exchange rates, yet these theories falter as they are based on challengeable assumptions [e.g., free flow of goods, services and capital] which seldom hold true in the real world.
One way to deal with the foreign exchange risk is to engage in a forward transaction. In this transaction, money does not actually change hands until some agreed upon future date. A buyer and seller agree on an exchange rate for any date in the future, and the transaction occurs on that date, regardless of what the market rates are then. The duration of the trade can be one day, a few days, months or years. Usually the date is decided by both parties. Then the forward contract is negotiated and agreed upon by both parties.

Flights to quality: Unsettling international events can lead to a "flight-to-quality", a type of capital flight whereby investors move their assets to a perceived "safe haven". There will be a greater demand, thus a higher price, for currencies perceived as stronger over their relatively weaker counterparts. The US dollar, Swiss franc and gold have been traditional safe havens during times of political or economic uncertainty.[76]

Trading in South Africa might be safest with an FSA regulated (or registered) brand. The regions classed as ‘unregulated’ by European brokers see way less ‘default’ protection. So a local regulator can give additional confidence. This is similar in Singapore, the Philippines or Hong Kong. The choice of ‘best forex broker’ will therefore differ region by region.
Economic numbers: While economic numbers can certainly reflect economic policy, some reports and numbers take on a talisman-like effect: the number itself becomes important to market psychology and may have an immediate impact on short-term market moves. "What to watch" can change over time. In recent years, for example, money supply, employment, trade balance figures and inflation numbers have all taken turns in the spotlight.
So, yes, at any given trading center, it's an eight hour day. But that really doesn't matter, because somewhere in the world trading centers are open. You can trade anytime you want, although you should also note that you'll get the narrowest spreads -- the broker's profit margin -- when the maximum number of trading centers are open or, more precisely, when the trading volume for your currency trade is greatest. 
There are two main types of retail FX brokers offering the opportunity for speculative currency trading: brokers and dealers or market makers. Brokers serve as an agent of the customer in the broader FX market, by seeking the best price in the market for a retail order and dealing on behalf of the retail customer. They charge a commission or "mark-up" in addition to the price obtained in the market. Dealers or market makers, by contrast, typically act as principals in the transaction versus the retail customer, and quote a price they are willing to deal at.
It should be noted that there is no central marketplace for the Forex market; trading is instead said to be conducted ‘over the counter’; it’s not like stocks where there is a central marketplace with all orders processed like the NYSE. Forex is a product quoted by all the major banks, and not all banks will have the exact same price. Now, the broker platforms take all theses feeds from the different banks and the quotes we see from our broker are an approximate average of them. It’s the broker who is effectively transacting the trade and taking the other side of it…they ‘make the market’ for you. When you buy a currency pair…your broker is selling it to you, not ‘another trader’.

Experts say that forex is a zero-sum game. That means that someone always loses commensurate to someone else’s win — that’s how the game is played. When you add in costs and fees associated with running a forex account and making trades, you enter negative-sum territory. That said, shrewd trading moves can pay out. Substantially. If you have the time and interest required to learn to identify patterns in price fluctuations and execute far-sighted trades, you will make wins on the forex market. That said, the most thoughtful strategy is also liable to bring about loss. Don’t trade more than you can afford to lose.
When the USD is listed second in the pair, as in the EUR/USD or AUD/USD, the value of the pip is fixed. If you hold a 1000 micro lot, each pip movement is worth $0.10. If you hold a 10,000 mini lot then each pip is worth $1. If you hold a 100,000 standard lot then each pip move is worth $10. Pip values can vary by price and pair, so knowing the pip value of the pair you're trading is critical in determining position size and risk.
The international governance regime is a complex and multilayered bricolage of institutions, with private institutions playing an important role; witness the large role for private institutions, such as credit rating agencies, in guiding the markets. Also, banks remain the major players in the market and are supervised by the national monetary authorities. These national monetary authorities follow the international guidelines promulgated by the Basel Committee on Banking Supervision, which is part of the BIS. Capital adequacy requirements are to protect principals against credit risk, market risk, and settlement risk. Crucially, the risk management, certainly within the leading international banks, has become to a large extent a matter for internal setting and monitoring.
Forex, also known as foreign exchange, FX or currency trading, is a decentralized global market where all the world's currencies trade. The forex market is the largest, most liquid market in the world with an average daily trading volume exceeding $5 trillion. All the world's combined stock markets don't even come close to this. But what does that mean to you? Take a closer look at forex trading and you may find some exciting trading opportunities unavailable with other investments.