​UPDATED: Check out “git difftool” which makes this process much cleaner (than the commands I previously had listed here). Basically, you can tell git what to use as a diff tool and it’ll let you do things like:

Here is how I tell git to use vimdiff (these settings go in ~/.gitconfig):

Here are some helpful commands that will get you started with vimdiff.

• ctrl+w ctrl+w – switch windows
• do – diff obtain (grab from the other side)
• dp – diff put (move to the other side)
• [c – previous difference
• ]c – next difference
• :diffupdate – (updates the diff)
• :syntax off – syntax off
• zo – open folded text
• zc – close folded text

Lastly, I suggest using the peaksea colorscheme when using vimdiff. It makes it much easier to see the changes and work with them.