Applying conditional formatting with formulas
You can use formulas to apply conditional formatting in Excel.
Begin by selecting the range you want the conditional formatting applied to. On the Home tab, select Conditional Formatting . . . New Rule.

In the 'Select a Rule Type' list, choose 'Use a formula to determine which cells to format'. In the box labeled, 'Format values where this formula is true:" enter a formula such as, "=$D2>=$H$3" This will apply the formatting to all values in column D greater than a target value entered in cell H3. Then click on the Format button and make the desired settings.
Excel applies the formatting to all rows in the selected range for which the value in column D meets the stated criteria.

Note when applying a rule be sure not to select the column headings and point the formula to the first cell holding actual data.