vimdiff usage

Ctrl-w w go to next window
Ctrl-w l : if you're in the left column and want to be in the right
Ctrl-w h : if you're in the right column and want to be in the left
]c : next difference
[c : previous difference
do : diff obtain, bring changes from the other file to the current file
dp : diff put, send changes from the current file to the other file
zR : unfold all lines
zr : open all folds
zm : close all folds
:diffupdate : re-scan the files for differences
:diffoff and :diffthis : allows you to turn the diff of a window off/on
:syn off : remove syntax highlighting
:q : quit (close current window)
:qa : quit all (close both files)
:qa! : force quit all