Listing color variants as separate products on a collection page

[lindley]

Hello, I am using the dawn theme and I am trying to figure out how to list one of my products , such as a shirt, which has different colors : olive, pink, blue, exc, as a separate listing, on my shirts collections page for example. I know theres a way to code such things but I have no idea how. I found other forms however, the themes differ as such the code for their theme does not correspond to the dawn theme, can anyone help? thanks