Help with multiple product variations

I’m creating a eCommerce websiste that will see Cowboy Silk Rags. Each rag (bandana) has size and color variation. When someone chooses a size I need to show only those colors that are sold for that size. Different sizes have different prices but color does not affect the price. I can’t seem to figure out how to allow the user to pick the size and then only have the colors associated with that size show up to choose from.

Right now I have set up multiple products based on their size but it would be nice to just set up one product and be able to choose the size and color you want.

Can anyone help me with this?

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