If you choose to create a post that includes product(s) with multiple variants, you can choose to set a specific variant as a default. Follow this step by step guide to walk you through how to set a variant as a default.
First log into your pear, then select the plus sign at the bottom of the page.
Select create a new post
Add products to the post by selecting select products
You can select the product(s) you wish to add by checking the box at the top right of the product
Once you have selected the product(s) you wish to add, select add product(s)
Then select customize products
Select the show more drop down to show more options
Select the set as default variant checkbox
Then select save
Complete your shoppable post by following the How to create shoppable posts guide.
Then publish! Your post will now default to the set variant anytime someone clicks on the product within this post.