On computer, copy BETA-SuperSU-v2.68.zip file to SD card.
On phone, go to Settings –> Developer Options –> Check the Manufacturer unlock : This will turn off a lock
On phone, hit the Volume Down+Power+Home at the same time This will Initiate Download mode on Grand Prime
Step 2. Use Odin
On computer, open Odin. Connect your Phone to PC : Odin will recognize your device in Download mode
On Odin, click AP –> choose recovery.tar.md5 file –> click ‘Start’ on Odin. Odin will start working and your phone will auto-reboot when it finishes
Step 3. Install SuperSU
On phone, hit the Volume UP+Power+Home –> slide the bar to continue : This will enter TWRP (recovery)
On TWRP, click install –> choose BETA-SuperSU-v2.68.zip file in SD card –> slide the bar –> hit restart : This will install SuperSU and phone will restart
4. Optimize your root
On phone, open SuperSU app –> click PLAY STORE (to update/install via Play store) —> hit update/install (in Play store).
Open SuperSU app again –> Update Normal –> hit Restart phone.
This finishes the last step of rooting. Your phone is rooted!