1. Download OpenGapps (ARM->(android version) -> micro) on your mobile
2. Download Cynogenmod according to android version and device kernel on your mobile (e.g cm-13.0-20160304-UNOFFICIAL-serranodsdd).
3. Boot your Samsung Galaxy device in TWRP recovery mode
- Switch off your device.
- Press and hold “Home + Power + Volume Up” buttons for a few seconds and as soon as you see your device’ logo on-screen, release three buttons altogether. Your device will boot into TWRP recovery.
4. Swipe to allow modification
5. Wipe data (format data)
6. Back <
7. Select Install
8. Select Storage and install CM 13/12
9. Swipe to confirm the installation
10. Wipe Cache/Dalvik
11. Now install OpenGapps
12. Wipe Cache/Dalvik
13. Reboot system