Remember: your income need not be large, so long as it is regular and enables you to put aside a surplus after you have taken care of your bills and the possibility of trouble. The surplus need not be large, either. Saving, as has been said many times, is a matter of regularity.
No one considers five dollars too small an amount to put into a savings bank; don't worry if that's all you can save each week for your accumulating investment reserve. In most markets, brokers usually can suggest a number of sound, solid stocks, offering liberal yields, that sell for less than twenty dollars per share.
There is no rule about the number of shares an investor must buy.
The forex market on the other hand is the worlds largest market to trade so due diligence is most important. Each country can adjust their currency prices to reflect the supply and demand for their products. When you are trading and watching your charts news can effect the supply and demand for that forex pair.