Here is a step by step guide to root T-Mobile Galaxy S Blaze 4G (SGH-T769) on Android 2.3.6 Gingerbread. And the following guide is originally taken from the XDA member forum, precisely from k0nane instructions.
You may follow the following instructions at your own risk. So let's get started.
Step 1: Firstly please download these files:
Step 3: Now enable auto-reboot on main menu. But uncheck any other options first -- and don't forget to uncheck Repartition option.
Step 4: Click your PDA from ODIN, then choose the Tar file downloaded from Step 1.
Step 5: Now click on PIT, then choose the PIT file you have downloaded from Step 1.
Step 6: Turn off your phone.
Step 7: Plug your Phone's USB cable to your computer, but don't connect it to your phone.
Step 8: Now take your off your phone's battery, then reinsert the battery.
Step 9: Do the following, press and then hold these buttons together: Volume Up + Volume Down + Power buttons while at the same time connecting your phone to your computer.
Once you have booted into Download Mode, you can release the buttons.
Step 10: You should now see your phone is detected by ODIN. However in some case, it doesn't detect then you can update your phone drivers -- from Samsung -- then try again the steps from 6 to 9.
Step 11: Now click START from ODIN.
Your phone will be rooted automatically!
Flash ClockworkMod Recovery
You have your T-Mobile Galaxy S Blaze 4G rooted, therefore it's time to flash ClockwordMod recovery. Do so by download these files:
And then follow the steps 4 until 9 to boot into Download Mode. And finish your steps by starting ODIN to start flashing!