Update Note 4G to Marshmallow || Installing Any Custom ROM on Redmi Note 4G (dior) || Resurrection Remix ROM || Android Marshmallow 6.0.1

You will need root and custom recovery on your phone.

Visit This Link to Easily Root Your Note 4G -> Installing Custom Recovery and Root Redmi Note 4G

After you are done rooting and Installing Custom Recovery, continue :

1) Download Resurrection Remix ROM (or any other ROM that you want to install)

2) Place it in your phone's SdCard and reboot to recovery by pressing Volume Up + Volume Down + Power Buttons at the same time.

3) Select Wipe and swipe to Wipe data. Go to "advanced" and select "wipe dalvik cache".

4) Select "Install Zip" and navigate to where you placed the ROM zip file. The installation will start.

5) After installation is complete, wipe dalvik cache again.

6) After you are done, reboot the phone.

Note : Most custom ROMS need Gapps to be installed according to what base android version they have. Flash the Gapps zip in similar way except don't wipe anything. If you don't flash Gapps, you won't be able to use Play Store and Services.