Left-click on the "Insert" tab.
Left-click on "Shapes." A drop-down menu will appear that shows the preprogrammed call-outs, also known as bubble shapes.
Left-click on the desired bubble shape.
Left-click the spreadsheet in the desired bubble shape location. The bubble shape will appear in a lined box with a small square in each corner, four small circles around the bubble shape, a yellow diamond shape and a green circle on top.
Move the mouse cursor over the small square in the bottom right hand corner. An arrow will appear. Left-click the mouse on the small square and drag it to make it larger.
Move the mouse cursor over the small green circle. Left-click the mouse on the green circle. Move the mouse to rotate the bubble to the desired location.
Move the mouse cursor over the yellow diamond shape. Left-click the mouse on the yellow diamond shape. Move the cursor to change the length of the bubble point.