The one basic rule to work with data in excel

If you decide to work with Excel there are several things you have to think of when you start. Believe it or not,but you have to keep in mind only one rule: Keep the layers separated!

Layer 1: data
Layer 2: operation (calculations)
Layer 3: representation (results)

I also tend to mix up this logical layers but by separating the data, the operational view and the representational view you will have some things easier lateron, e.g.: As your data layer doesn't have an impact on your representation layer, the adding of data columns does not alter the dashboard or representational view.

So the layering and separation will help you in maintaining your excel charts, it will make you  more flexible and the documentation a lot more easier.

But I can tell you right away: You will have to learn some things fast. Amongst these things are matrix formulas, the indirect functions and various lookups. Is there anything you want to add?