To set the cell's background color, use the attribute bgcolor of the <td> tag. Set
its value to the name of the color: blue, red, orange, white, yellow,... or set it to its hexadecimal value
like this: #00FF00, #CCFFDD, #000000, ..... You can also set the color in its RGB value, like this: RGB(10,255,0) for example.
To set an image as a cell's background, use the background property of the <td> tag. Set the property value to the path of the image you want to load as a table's background.