1. Press Power button until the phone turns off.
2. Next, press and hold these buttons simultaneously: Volume Up and Down & Bootloader & Power buttons until the Samsung logo appears on screen.
3. Now press Volume Down twice to select Recovery mode. Enter it with a press of a Power button.
4. Release Power button when the android robot pops on-screen.
5. You now should be in Recovery Mode. Here, use Volume and Power buttons to navigate.