This is just a condensed version of:
https://github.com/munki/munki/wiki/Demonstration-Setup
1. Install XCode
2. Install latest Munki
3. cd /Users/Shared/
mkdir munki_repo
mkdir munki_repo/catalogs
mkdir munki_repo/manifests
mkdir munki_repo/pkgs
mkdir munki_repo/pkgsinfo
chmod -R a+rX munki_repo
4. sudo ln -s /Users/Shared/munki_repo /Library/WebServer/Documents/
5. (Sysrem prefs -> sharing -> set a sane hostname, turn on Web Sharing)
6. /usr/local/munki/munkiimport --configure
Path to munki repo (example: /Volumes/repo): /Users/Shared/munki_repo
Repo fileshare URL (example: afp://munki.example.com/repo): <just hit return>
pkginfo extension (Example: .plist): <just hit return>
pkginfo editor (examples: /usr/bin/vi or TextMate.app): TextWrangler.app
Default catalog to use (example: testing): main
7. /usr/local/munki/munkiimport ~/Downloads/Firefox\ 33.0.2.dmg
8. Follow prompts.
9. /usr/local/munki/manifestutil
Entering interactive mode... (type "help" for commands)
> new-manifest test_munki_client
> add-catalog main --manifest test_munki_client
Added main to catalogs of manifest test_munki_client.
> add-pkg Firefox --manifest test_munki_client
Added Firefox to section managed_installs of manifest test_munki_client.
> exit
10. sudo defaults write /Library/Preferences/ManagedInstalls SoftwareRepoURL "http://localhost/munki_repo”
sudo defaults write /Library/Preferences/ManagedInstalls ClientIdentifier "test_munki_client"
11. sudo /usr/local/munki/managedsoftwareupdate