Click the arrow at the right side of the formula bar. Go to the Excel options Advanced Display Show formula bar. Insert Function dialog box.
Enter cell references with pointing.
For an example of editing a long formula in an expanded formula bar watch this video. See screen shot below. Tick or untick the rectangle box given to enable or disable the formula bar. To edit any data and formula in any cell select the cell and either click into the Formula Bar or press F2 to enter editing mode.