Magento is a powerful framework, but sometimes it isn’t the easiest to figure out. As someone new to Magento 2 development, I find myself relying on the online community to learn how to do the things I need for my job. I recently wanted to find a way to change my site’s theme to my custom theme. I found many tutorials on how to do so through the admin panel, but I wanted a way to make this change programmatically. That way new instances I install would have my new theme as the default, and I would not need to manually change it every time. As I could not find those instructions online, I humbly offer my findings here. Hopefully it will help someone!