Under Format rules, select Custom formula is. Then go to the menu: Format > Conditional formatting. Highlight your data range, in this case, A2:C21 (omitting the header row). How To Highlight The Top 5 Values In Google Sheets Method 1: Use the LARGE Function. This will apply a basic alternate color scheme to each row of your data set and open the. After your data is selected, click Format > Alternating Colors. You can either do this manually or select a cell in your data set, and then press Ctrl+A to select the data automatically. To do so, open your Google Sheets spreadsheet and select your data.