Backtesting is a kind of a strategy test performed on the past data. It can be either automated or manual. For automated backtesting, a special software should be coded. Automated testing is more precise but requires a fully mechanical trading system to test. Manual testing is slow and can be rather inaccurate, but requires no extra programming and can be done without any special preparation process. Any backtesting results should be taken with a grain of salt as the tested strategy might have been created to fit particular backetsting historical data.
Trend-following systems require a particular mindset, because of the long duration—during which time profits can disappear as the market swings—these trades can be more psychologically demanding. When markets are volatile, trends will tend to be more disguised and price swings will be greater. Therefore, a trend-following system is the best trading strategy for Forex markets that are quiet and trending.