You have a table that has a cell with text, a cell with an image, and a cell with a caption. One style for the entire table is not going to work. You are going to have to individually style each cell. Don't fret, once you understand how to do it, it will be a piece of cake and your mailing will look great!
Place the cursor in the table cell.
Select the td tag found in the HTML tag navigator section of the editor.
When selected, the table cell will appear to have a blue border around it.
With the table cell highlighted, click the CSS toolbar button to open the style dialog.
Apply the desired styling to the table cell.
The format we applied is specific to the cell we had highlighted with the td tag.
Knowledge is Power
You can now format any of the other cells in the table. Your mailing is going to look great!