- Double-click on the cell you want to add a SUM function to. In this case, we'll double-click on cell D12 and type =SUM(
- Click on cell D2 to create a cell reference in the formula.
- Move the cursor to the bottom right of cell D2 until it turns into a double arrow.
- Click, hold, and drag the double arrow until you highlight cells D2 to D11.
- This will create a range of cell references within the SUM function. Add a right parenthesis, and the SUM function will look like this: =SUM(D2:D11).
- Press the "Enter" or "Return" key on the keyboard, and the SUM function will calculate.
