Upgrade flame and install Myanmar keyboard.

gistfile1.txt

1.
Enable developer menu.
  Settings -> Device information -> More Information -> Developer Menu (enabled)
  Settings -> Developer -> Debugging via USB (select ADB and DevTools)
(Note: adb can't access the device while it is in locked state.)

2.
Download and update base image (Base image v188.zip) from
https://developer.mozilla.org/en-US/Firefox_OS/Phone_guide/Flame/Updating_your_Flame

  Use flash.bat 
    $ . flash.bat 

  Or rename flash.bat to flash.sh
    $ mv flash.bat flash.sh
    $ chmod 755 flash.sh
    $ ./flash.sh

3.
Enable developer mode as step 1.
Then download and flash "Latest v2.2 builds" (User or Eng) from
https://developer.mozilla.org/en-US/Firefox_OS/Phone_guide/Flame/Updating_your_Flame
  Download shallow_flash.sh and update b2g and gaia to device
    $ ./shallow_flash.sh --gaia=gaia.zip --gecko=b2g-37.0.en-US.android-arm.tar.gz

4.
Download and install myanmar keyboard
  Using git
    $ git clond https://github.com/Seinlin/mm-kb.git -b v2.2
    $ cd mm-kb
    $ . INSTALL

  Or download zip file and run 'INSTALL'
    https://github.com/Seinlin/mm-kb/tree/v2.2

5.
Enable myanmar keyboard and have fun!
  Settings -> Keyboards -> Select Keyboards -> Select Myanmar


NOTE 1 - 
In latest master build (Step 3), Myanmar keyboard is included.
So if you are using master build, step 4 can be iganored.
But mater branch is under developing, so there could be some problem.
Suggest to use v2.2, which is the latest stable release.

NOTE 2 - 
In nightly build, firmware upgrade is available every day, you can modify the check update frequency in settings.
  Settings -> Device information -> Check for Updates (Select to Monthly could be more convenient to use.)