If this layout isn’t exactly what you want, you can modify it by using other options in the Layout Tables task pane. For instance, suppose that we want to divide the first of the three columns into two rows.
To do this, we first select the column that we want to modify. This will not cause the column to become highlighted or look different in any way. The best way to make sure that you made the correct selection is to check that the cursor is now in that column.
Next, click on Insert Layout Cell from the New tables and cells division of the Layout Tables task pane.

click to enlarge
This will open the Insert Layout Cell dialog box as shown below.

click to enlarge
If you know the exact dimensions of the cell you wish to create, you could enter them at this point. If not, just click OK and a cell of default size will be added to your table layout.

click to enlarge
Use your mouse to drag the edges of the new cell until you reach the desired height and width.

click to enlarge
Repeat this process as many times as needed to create any additional cells for your table layout.
For more tips and tricks, be sure to take a look at the other items in Bright Hub's collection of Expression Web user guides.