You can edit the cells in a row in sequence by tabbing from one to the next.
TAB to move to the next cell;
SHIFT TAB to move to the previous cell (i.e., tab backwards).
Arrow keys
You can also edit neighboring cells by CTRL ARROW (UP, DOWN, LEFT, RIGHT).
Tab vs. Arrow keys
Pressing the TAB key repeatedly causes the cursor to cycle through the cells of the same row, whereas the arrow keys allow you to edit cells in different rows and columns.
