How to Change the Text or Background Color of a field in a Table or Pivot Table?
You could enable View->Design Grid
Then right click a cell in the column you want to change color / Text style for and select from context menu Custom Format Cell.
This dialog should be quite easy to use.
You can also apply style changes using attribute expressions. You find the attributes if you click on the plus sign next to the dimensions / expressions in dimension and expression tab. Select e.g. background color and enter as expression a color expression, e.g.
Another way is to use visual cues from the Visual cues tab in chart properties, e.g. to highlight certain values.