1) Put `tlskeylogger.plist` at `~/Library/LaunchAgents/tlskeylogger.plist`
2) `launchctl load ~/Library/LaunchAgents/tlskeylogger.plist`, so it will load on the next restart
3) `launchctl start ~/Library/LaunchAgents/tlskeylogger.plist`, so it will load the environment variable immediately
4) Restart your browser(s)