Conditional Formatting a data series in a graph.

I need some help with some conditional formatting if you don’t mind. I have a spreadsheet (I attached it). It is a stacked bar chart. I want to make each letter a specific color for example, for all the H’s I want it to be one color, for all the HL’s I want it to be one color, for all the A’s one color. I have been trying and trying but I cant seem to get it. Would you please help me.


Thanks!