You can also add additional series to the chart. For example you’ll see I’ve added another series from the data in Column F:

Go to the main menu item ‘Chart’ (which comes up when you have the chart selected). Then go to ‘Source Data’ you will get the submenu shown below:

Now go to the 'Series' tab. When you press ‘Add’ it will add ‘Series2’ but the ‘X Values’ and ‘Y Values’ will be blank. Select the ranges containing the values you want to add, then ‘OK’   Roll your mouse over the image to see the last step.