Product color from select list in Commerce Kickstart 2
That's exactly what variations are for...

You have a product (a t-shirt) with a variety of different options (colours), hence you need different variations of the product to identify what colour of t-shirt has actually been sold.

Kickstart already has that exact functionality built right in; if you install the demo content and browse to "/tops/guy-short-sleeve-tee" you should see it: