If you haven't already done so, can I suggest you have a read of this Tableau blog entry
and watch this Tableau training video Clustering
They should help you get a better understanding.
If you then have a particular problem you're trying to solve, then please post a question in the main Desktop Tableau Forum here Forums , providing as much detail about what you're trying to achieve, and show via a packaged workbook what you've managed to do so far.
Thank you for your suggestions.
I will try it but I couldn't watch that video....