When backtesting we simply select a timeframe and setup we wish to test (ie on the EURUSD), then review its past chart action to see how it performed. This isn’t a completely fail safe method (as it shows past behaviour, not future) but it gives us a good idea of what we can expect from our strategy. As a general rule I find around 150-200 trades good (approx 8 hours work). We want this large number for 2 reasons. Firstly to filter out any odd results, and secondly to become an expert... We have to place, calculate and record the risk of 200 entries, stop losses and trailing stops (if applic). Trading is not an art, it’s a science. Repetition makes us better. We start on the chart by marking each trade entry and putting 2 numbers by it, 1. The "Risk" in pips (Entry - SL). 2. The "Profit/Loss" in pips (Exit - Entry).
Once we have done this for 200 trades we open a spreadsheet. On the horizontal axis we input, "Date/Trade#", "Risk(pips)", "P/L (pips)"," P/L %" and "Total %". We then input the date and trade number in "Date/Trade#" column, the first number from each trade (on your chart) into the “Risk” column, the second number into the “P/L” column, and then divide “P/L” by “Risk” to get the "P/L%". Finally we add up all the "P/L%s" from the given day (week if swing, month if position) and place that number in our “Total %” column.
This gives us ample data to help create an income (ie Net P/L, win/loss %, biggest win, average win, average loss etc). We don’t cut corners, it’s the repetition that makes us experts, gives us reliable data and creates self trust!
Once we have done this for 200 trades we open a spreadsheet. On the horizontal axis we input, "Date/Trade#", "Risk(pips)", "P/L (pips)"," P/L %" and "Total %". We then input the date and trade number in "Date/Trade#" column, the first number from each trade (on your chart) into the “Risk” column, the second number into the “P/L” column, and then divide “P/L” by “Risk” to get the "P/L%". Finally we add up all the "P/L%s" from the given day (week if swing, month if position) and place that number in our “Total %” column.
This gives us ample data to help create an income (ie Net P/L, win/loss %, biggest win, average win, average loss etc). We don’t cut corners, it’s the repetition that makes us experts, gives us reliable data and creates self trust!
Finally forward testing requires us to trade the strategy in real time using either a demo or micro account (we're not fully invested!). This allows us to practice and learn how to implement it in reality while fixing errors that a moving market with slippage will create, believe me there will be errors! Once we have tripled our demo account we can fully invest.