how to add a new indicator to metatrader 4?

 
hello to everybody i need help in adding the doncian indicator to metatrader4 please if anybody can leave me some simple instructions how to do that?i have allready downloaded it but i cant understand how to add it to the metatrader4 and start using it with the meta4!!!thanks for the help!!shalom!
 
Try to move this indicator on the chart.
Reason: