First your rom need to be rooted and with a custom kernel + CWM
Copy the file inside your device (internal or external memory)
So, supose you have all above reboot your phone into recovery mode, choose install menu or something like, install from sd card (internal memory) or install from external sd card (memory card) than find the file in a place that you have put and install.
Wait the process and reboot system.
The merit in having hardware buttons on Android is a highly … more
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