The following steps can be done by going to Design › Featured Categories in your eCom back office.
Setting the Featured Categories
To choose what categories are featured on the homepage, go to Design › Featured Categories and click on Add Category. This will pull up a list of your shops categories. Choose either 3 (one row) or 6 (two rows) to maintain uniformity in the design. The Austin theme allows for up to 6 featured categories.
Category images
Displaying the Featured Categories
Select the Categories option for any of the homepage sections (this is done by going to Design › Edit Theme › Pages › Home Page › Home Content Order).
To make sure your category images are uniform in size and alignment, be sure to have the Auto align category images setting turned ON (this is done by going to Design › Edit Theme › Pages › Category details › Image Settings).