If you select your input range first (say A12:D99), and change
tools|options|Edit Tab|Move selection after Enter to Right (or turn it off)

Then tabbing/entering will follow your desired path.

John wrote:

I am entering data on a worksheet from left to right, using the tab. At the
end when I hit Enter, I want the very first cell on the next row to be where
I start. I have looked at Options-General, but it only will determine "Up,
Down, Left, Right". I would like to set it to where the Home begins on the
first cell of the next row.

--

Dave Peterson