Click on the market icon on your MT4/mt5:
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 Click on Indicators and you can also use the search bar to type and search the indicator example type "Smart Trend Trading System":
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Select the Indicator you want and click buy and follow steps of purchasing using your preferred payment method:
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After purchase you will see Install and open Button, typically Install button first after the install you will see the open button:
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After install and open you will see the indicator name in the navigator:Â Â 
Click and drag the indicator to the desired chart:
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you can navigate to inputs to see all the input settings of the indicator:
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Also you can navigate to colors where you can change the colors of the indicator, certain colors can be changed in the inputs bar for easier access:
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Click OK and the indicator will be applied, now the indicator is ready:
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