Easiest way to create a persistent Guest account on Mac OS X (tested on Mavericks and Yosemite)

persistentGuest.md

1. Create a new Standard User (name it ex. Blah),
2. Log in as this user and setup account as you want it to be for Guest,
3. Log out,
4. Log in as any administrator (for root skip sudo),
5. Execute those commands:

sudo rm -rf /Users/Blah/Library/Caches/*
sudo rm -rf /Users/Blah/Library/Keychains/login.keychain
sudo rm -rf /Users/Blah/Library/Preferences/SDMHelpData
sudo rm -rf /Users/Blah/Library/Saved\ Application\ State/*
sudo rm -rf /System/Library/User\ Template/English.lproj
sudo ditto -V /Users/Blah /System/Library/User\ Template/English.lproj
sudo chown -R root:wheel /System/Library/User\ Template/English.lproj

6. Remove user created in #1 step (Blah),
7. Done.

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