Do you want the history of all color formulas that a customer ever had? When a customer asks for the color formula of last year, do you want to be able to find it?
This can easily be done via
1. Customers
2. Find the customer on a.d. the name
3. Click on the name of the customer
4. Click on the category "colorings"
5. Click on create
6. Fill in the new color formula
7. Press "Save"