You can highlight cells based on specific values using Conditional Formatting in Excel. Here's how:

1. Select the cells you want to format: Choose the range of cells you want the rule to apply to.

2. Go to Conditional Formatting: Navigate to the "Home" tab on the Excel ribbon. In the "Styles" group, click on "Conditional Formatting."

3. New Rule: A dropdown menu will appear. Select "New Rule" to create a new formatting rule.

4. Format only cells that contain... In the "New Formatting Rule" window, choose the option "Format only cells that contain..." This is the most common option for highlighting based on values.

5. Set the criteria: Here's where you define the condition for highlighting:
- Select a comparison: Choose the comparison operator you want to use. Options include "greater than," "less than," "equal to," "between," and more.
- Enter the value: In the box next to the comparison operator, enter the specific value you want to compare against.

6. Format with: Choose the formatting you want to apply to cells that meet the condition. You can change font color, fill color, borders, or other cell styles. Click the "Format" button to customize the formatting options.

7. OK: Once you've set the criteria and formatting, click "OK" to apply the conditional formatting rule.

Now, any cells within the selected range that meet your specified criteria (e.g., greater than a certain value) will be highlighted with the formatting you chose. This allows for quick visual identification of cells based on their values.