Here's how you can highlight the date in Cell E3 if it's within 30 days of today's date:

1. Select the cell E3 where you have the date that you want to highlight.
2. Click on the "Conditional Formatting" option in the "Home" tab of the Excel ribbon.
3. Select "New Rule" from the drop-down menu.
4. In the "New Formatting Rule" dialog box, select "Use a formula to determine which cells to format".
5. In the "Format values where this formula is true" field, enter the following formula:
   Code:

   =AND(E3-TODAY()=0,E3-TODAY()<=30)

   This formula will check if the date in E3 is greater than or equal to today's date and less than or equal to 30 days from today's date.
6. Click on the "Format" button to choose the formatting you want to apply to the cell. In this case, you can choose the "Fill" tab and select the yellow color.
7. Click "OK" to close the "Format Cells" dialog box.
8. Click "OK" again to close the "New Formatting Rule" dialog box.

Now, the date in Cell E3 will be highlighted in yellow if it's within 30 days of today's date. You can also copy and paste this formatting to other cells with dates that you want to highlight in the same way.