Edit cell contents

Double-click the cell that contains the data you want to edit.

Edit the cell contents.

To enter or cancel your changes, press ENTER or ESC.

To turn editing directly in cells on or off, click Options on the Tools menu, click the Edit tab, and then select or clear the Edit directly in cell check box. You can edit in the formula bar when the Edit directly in cell check box is cleared.
To move your cursor to the end of the cell contents, select the cell and press F2.