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Think of Data Validation as a way to assist people to filling out the form correctly. They act like post it notes or hints with little instructions. When using Data Validation, be sure to give a clear message and provide all relevant information.
To use Data Validation,
Create your form and click in one of the fill in boxes.
Click the Data Tab, then choose Data Validation
In the Data Validation Box, choose Input Message. Then type in some instructions that will help the reader with the form. Click OK. Your end result should show a yellow square with your instructions inside it.
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