com.example.testing.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
	<dict>
		<key>Label</key>
		<string>com.example.testing</string>
		<key>ProgramArguments</key>
		<array>
			<string>/usr/local/bin/testing.sh</string>
		</array>
		<key>RunAtLoad</key>
		<true/>
	</dict>
</plist>

testing.sh

#!/bin/bash

logger "#######################"
logger Current user: $(whoami)
logger "#######################"

exit 0