How do I use the colour shop?

This is the name of the store.
When you want to purchase a colour, this button will activate it. After you’ve activated it, you’ll be able to purchase the colour by tapping on it again.
The colours are grouped according to what items the colours are used on. From up to down: Clothing colours, hair colours, eye and makeup colours, and furniture colours.
The number of coins and diamonds you have are displayed here.