Auto-fit

When a Table is set to Auto-fit, it will automatically resize the cells, rows, and columns to fit the content on the slide. 

Manual

Row or Column

To manually adjust a row or column, click and drag the Row or Column Header divider.

Entire Table

To manually adjust the entire width and height of your table, click on the table to bring up the Resize  buttons. Click and drag the Resizers to change the width and height.