How to make Kaleidoscope your default Git Diff and Merge tool

First you need to grab the ksdiff command line tool and install it

https://www.kaleidoscopeapp.com/ksdiff2

Then the following set of commands will set kaleidoscope to be your default diff/merge tool

git config --global diff.tool kaleidoscope
git config --global difftool.kaleidoscope.cmd '/usr/local/bin/ksdiff --diff "$LOCAL" "$REMOTE"'
git config --global merge.tool kaleidoscope
git config --global mergetool.kaleidoscope.trustExitCode true
git config --global mergetool.kaleidoscope.cmd '/usr/local/bin/ksdiff --merge "$LOCAL" "$REMOTE" --base "$BASE" --output "$MERGED"'

Then to run it

$ git difftool FILE1 FILE2
$ git mergetool