LG Aristo SuperSU Root –
By now you must have downloaded the “UPDATE-SuperSU-v2.82.zip” file and transferred to your Internal Memory/microSD card.
Click on “Install” and select the “sdcard1” folder as shown above.
If you’ve downloaded the file to internal storage you’ll find it in “sdcard” folder, the folder just above “sdcard1”
Click on the downloaded zip file i.e UPDATE-SuperSU-v2.82.zip
If you’ve already flashed Magisk, do not attempt to install SuperSU.
Swipe the bar towards the right to flash SuperSU.
Click on “Reboot System” to restart the phone.
Open the SuperSU app.
You can see SuperSU has got the old user interface with not many options. It cannot match Magisk in functionality. However, if you only need root access, it’ll fulfill your need very well.
If you’re facing any issues let me know via the comment section below.
Source : xdaforums