Yes, I can definitely help you with that. Here are the steps to make a cell red in Excel if it contains a negative number:
1. Select the cell or cells that you want to format.
2. Click on the Home tab in the Excel ribbon.
3. Click on the Conditional Formatting option in the Styles group.
4. Select "New Rule" from the drop-down menu.
5. In the "New Formatting Rule" dialog box, select the "Use a formula to determine which cells to format" option.
6. In the "Format values where this formula is true" box, enter the following formula without the quotes: "=A1<0" (change "A1" to the cell reference you're using).
7. Click on the Format button to choose the font color and fill color you want to use. Select red as the fill color and click OK.
8. Click OK again to apply the conditional formatting rule.
That's it! Now any cell that contains a negative number will be highlighted in red.
