Download CWM / TWRP installable ZIP from https://download.chainfire.eu/696/SuperSU/UPDATE-SuperSU-v2.46.zip
Boot into TWRP or CWM Recovery. TWRP or CWM Recovery has inbuilt ADB functionality, hence ADB commands work while in recovery mode. Connect the device with computer through USB cable and run following command.
adb push UPDATE-SuperSU-v2.46.zip /external_sd/
The file is now available on SD card. Flash and reboot
If you don’t have SD card then push the zip into internal storage with following command
adb push UPDATE-SuperSU-v2.46.zip /sdcard/
Don’t confuse with /sdcard , it actually points to the internal storage while /external_sd points to the external SD card.