Excel - Cell Formatting

Hi,

I want a cell to automatically be formatted in a certain colour when certain text is inserted, how do i do this. For example:

If the text entered into a particular cell is:

- Complete - then format the cell the colour green
- On Track - light green.
- Overdue - then format the cell the colour red
- At risk - then format the cell the colour amber

I've tried using Conditional Format which does if for the existing content. However, when i change the text i'd like the colour to automatically change as above