In a bull market, prices regularly rise on Monday, Thursday and Friday. While prices tend to fall on Tuesday and Wednesday. In a bear market, it is exactly the other way around.
If the opening price on a trading day is above the exponential moving average, we assume that it is a bull market. We therefore always go long on Monday, Thursday and Friday, and short on Tuesday and Wednesday. On Monday morning we buy a position and close it shortly before the closing bell rings. On the following Tuesday we sell short in anticipation of falling prices. We continue to follow this plan for the rest of the week.
If the DAX is below our trend filter at the opening of trading, we assume that there is a downward trend, i.e. a bear market. We apply the opposite behavior: on Monday, Thursday and Friday we short the market. Whereas on Tuesday and Wednesday we go long. If you apply this simple rule to the historical data, you should get a profitable and stable trading system.