Your collection page filtering can be customized from the Shopify Search and Discovery app. Using this app you can add new filters and customize how they appear on your theme.
Shopify has recently made a number of improvements to metafields and how they work with swatches. This is great news for us because now swatches are much easier to manage and update.
Go to Settings > Custom Data
Scroll down to Metaobject definitions then click Add definition
Add a name and description to your metaobject
Add three fields to your metaobject

We now have to assign values so data is populated for our new metafields.

You can add filters using color product options. This is a easy way to add filters but will require swatch files to be uploaded in a specific format. Swatches will only appear using this approach when the product option matches "color" - or a translation of color.
This is the same approach you would take if you wanted to filter by any other product option like size.
If you use metafield swatch filtering you'll have to ensure you update your metafields for all products that you want to appear on this filter - this will NOT happen automatically even if category metafields and variant options are displaying swatches.
Go to Online Store > Theme settings > Custom css
Within your custom css block paste the following code:
For color swatches/custom swatches (adjust the REM within height and width in increments of .1 for the best results) :
.btn.btn--plain {
height: 2.2rem;
width: 2.2rem;
}
Upload missing swatch files
You may notice that not all of your color filters are appearing with swatches. If this is the case you may have to upload custom swatch files.
Swatches will only appear automatically if the color name matches a default CSS color.

Start by connecting your source repository and choosing the pages you want to publish.
You can then browse your documentation and ask questions about the content your team has shared.