To format text for strikethrough in Google Docs, you can use the built-in Format > Text > Strikethrough option or press the keyboard shortcut Alt + Shift + 5 on Windows or command + shift + X on Mac. If using the mobile app, highlight the text and tap the Format icon to access the Strikethrough option. Additionally, Google Docs offers automation capabilities through Zapier, allowing users to connect their documents with other apps and automate tasks such as creating new prefilled documents.