Trendline is one of the widely used trading strategies for calculating support and resistance levels in forex trading. Mt4 and mt5 platforms provide built-in tool for drawing trendlines on forex charts. You will need to click on a slash (/) like icon on the tool bar as demonstrated in the following graphic: Once the trendline icon is selected, the mouse pointer will turn into trendline sign. Then you need to draw a trendline on chart as shown in the following video: http://screencast.com/t/8QBSHlyq You should connect as many candles as you can with a condition that the trendline should remain intact. In order to turn off the automatic drawing of trendlines, open the properties of trendline and uncheck the “Ray” option as shown in the following video: http://screencast.com/t/hBKxcRBVZXi Remember trendline trading strategy is successful only if it is used in conjection with other price action strategies such as swing trading, Fibonacci trading, MACD divergence etc.