Simple Urgent SMS Notifications with Google Sheets and Twilio allows users to send urgent messages to customers or staff without needing access to developers or usual tools. The tutorial requires a Twilio account, a Google or G-Suite account, and the ability to choose from different number types such as standard phone numbers, Toll Free Numbers, Short Codes, and Alphanumeric Sender IDs. To set up, users create a copy of the provided Google Sheet, enter their Twilio credentials, decide on a sending method, test the setup, send bulk messages by filling in greeting and message boxes, and check message status periodically. The script uses the REST API to send SMS messages and stores the initial status response for later checking. Users can troubleshoot issues by checking account details, numbers sheets for errors, and logs inside the Script Editor.