dual usb drive how to use

Just bought a dual  3.0 usb drive for my android motog2 ( 2014) phone. Also downloaded file manager and USBFM apps but I am totally lost how to transfer data from my phone to this drive. I am not able to. Please give me step by step instructions.

Thank you.

Hello,

first of all you have to make sure that the mobile phone supports the otg feature in order to be able to detect the drive as an external storage device.