As this the first Cm13 nightly of galaxy S II and no one yet test it there may be some bugs but don’t worry it should be fixed in next nightly.so we request you to test it out and report in the comment section.As this is first cm13 nightly there may be bugs in it I refer you to make the backup of your current rom.Let’s start the guide on How to install Official Cm13 rom galaxy S2.
Related Post: Official CM13 Rom For Galaxy S5/S5 Duos (China)
Make sure you have rooted and custom recovery installed in your device.TWRP recovery is recommended.
#How to install Cyanogenmod 13 Rom in Galaxy S2
1.Download official CM13 Rom for Galaxy S2 and the appropriate Gapps 6.0 package from the link given below Copy it in your in your device.
2.Now place the Cyanogenmod 13 rom and gapps 6.0 zip file in sd card.
3.Now reboot into TWRP Recovery mode
4.Then flash CM13 android marshmallow rom and gapps from the recovery in it.
5.Now Clear cache and Clear Data.
6.Reboot your device.Done! you just flash cyanogenmod 13 rom in your Samsung Galaxy S2.