Decision to buy or sell
Exchange rates are affected mostly by prevailing market forces of demand and supply per any given season. If at any given point the demand for a certain currency is high, its value will appreciate leading to an increase in its price. Also, if there is excess supply of a currency, it loses its value leading to a decrease in its selling price.
Speculations in forex trading are made by investors using fundamentals of trading anticipating movements in the price of an exchange rate. Factors to consider include, economic indicators, news-based events, automated forex trading signals, political and social data, past performance and general currency liquidity.