# Let's use the Finder's prefs file as an example

# Convert it to XML format
plutil -convert xml1 ~/Library/Preferences/com.apple.finder.plist


# After editing, convert it back
plutil -convert binary1 ~/Library/Preferences/com.apple.finder.plist

# Restart the Finder
killall Finder

A pair of handy terminal commands for converting Apple .plist preference files from binary to XML format [allowing for easy editing with a text editor] and then back to binary again, afterwards.

Convert Apple .plist file to from XML / binary

xml, osx, convert

Bash