Data Validation: Summary You can Autofill the Data Validation--including the Input Message and Error Alert--to the rest of the cells in Column A.   8. Try it: Autofill the Data Validation Select Cell A2. Delete the client name, if any. Cell A2 should be blank. Use the Autofill handle to copy and paste the Data Validation from A2:A12   Do This, Too: Save Your Work Go to File->Save. File Name: Your Name TimeSheet. Save. Save. Save. You done good. Data ->Data Tools-> Data Validation