To make your device ready for debugging you need to enable your device for debugging first. In order to enable your device for debugging in Developer options. To access these settings, open the Developer options in the system settings. On Android 4.2 and higher versions, the Developer options screen is hidden by default. To make it visible, go to Settings | About phone and tap on Build number seven times:
After this, return to the previous screen to find Developer options at the bottom:
Now, enable the USB ...