Karlie here from the Shopify Guru Team! Hope your day is going well! I would be happy to help you out with transferring ownership in your store!
First off, I would recommend going through your Shopify Admin and changing any settings that you'd like switched over to the new owner, like billing information, check the account that is connected to your payment gateway, be sure to check out the shipping address in your settings as well.
When you're ready, you can transfer ownership by heading into your Shopify Admin. You can follow these steps from your Shopify Admin to transfer ownership:
We have a really awesome step by step doc that I would recommend checking out as well, you can check it out here it will go over the details on how to change ownership and adjust staff member accounts from your Shopify admin. I hope this helps, but if you have any further questions - be sure to ask and we would be happy to help!