Add vi mode to your Bash prompt.

vi.inputrc

# add the contents of this file to ~/.inputrc

# this is where the magic happens
set editing-mode vi

# vi INSERT prompt
set vi-ins-mode-string "\1\e[30;44m\2 INS \1\e[0m\2 "

# vi NORMAL prompt
set vi-cmd-mode-string "\1\e[30;47m\2 NOR \1\e[0m\2 "

# bash is a nice place to mix and match vim and emacs, to find your personal style
$if mode=vi
    # bind substring history commands to j and k on vi's command mode
    set keymap vi-command
    "k": history-substring-search-backward
    "j": history-substring-search-forward

    # I can't live without C-l to clear the screen
    set keymap vi-insert
    "\C-l": clear-screen
$endif