you need to install a custom recovery first, you do that with fastboot. copy the recovery image into the same folder as fastboot and rename it to recovery.img. enter the bootloader with your phone connected to your pc
when in the bootloader use your volume to scroll and choose fastboot then hit power button. you should have fastboot usb highlighted at the top of the the list. now in your command window type;
fastboot flash recovery recovery.img
then type fastboot boot recovery
you should be good to go
That's the long way of doing it man.
Fond your choice of custom recovery you want. RA, CWM, or TWRP. Make sure you stay away from TWRP 2.0 as last I seen it had lots of bugs and bricked a few devices.
Once downloaded, rename zip file to PC36IMG.zip. make sure you don't name it PC36IMG.zip.zip on accident.
Place this file on the root of your SD card. (Root meaning in no folders)
Boot into fast boot and your phone will automatically search for the PC36IMG.zip file. Once it loads up, it will ask you to update. Volume up for yes, volume down for no.
Hit volume up to install update and it will flash your custom recovery.
Once update finishes hit volume down to decline a restart.
Volume down to recovery and select it with power button.
Boots into the custom recovery.
Make a nandroid backup first thing before you do anything to your phone.
Remember not to flash anything with at least 40% of battery life and nandroids only work on the recovery it was made on. Ie CWM backups will not restore through RA recovery.
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