Select the cell(s) in which you want the conditional formatting
Choose Format>Conditional Formatting
From the first dropdown, choose Formula Is
In the formula box, type a formula that refers to the cell you
want to check. For example, if the active cell is in row 2,
and you want to check the value in column A: =$A2>50
Click the Format button, and select the formatting for the cell
Click OK, click OK