1. Boot in to TWRP
2. go to Advanced / File Manager and delete folder named supersu
3. go to Advanced / Terminal and enter these two commands
echo SYSTEMLESS=true>>/data/.supersu
echo BINDSYSTEMXBIN=false>>/data/.supersu
The first one forces systemless, the second prevents /su/xbin_bind from existing.
4. Flashed Beta SuperSu 2.74-2 (we can notice while flashing this zip after the above script, we will not see the line saying "Disabling OTA". Also, end of flashing it warns that it takes longer time to boot.
5. Reboot device and enjoy systemless
6. To check if we have achieved systemless root, go to system/xbin folder and we should not see the file named "su".
7. I rebooted in to TWRP and flashed xposed 85.1 (also updated with 85.2 later) and installed the apk (Material design apk from this thread)
8. All done and my xposed works.....