Using one cell to enter data and move pervious data over

I want to use only one cell to enter data. Once I enter data a second time in the same cell I want the old data to move to the next cell on the right.

Example: I enter 3/12 in colum A cell 1. I click the enter button now it moves 3/12 to column b cell 1. Now I enter 3/19 in column A cell 1 click enter. Now 3/19 goes to column B cell1 and 3/12 moves to column C cell 1.