Please use the following instructions:
- Switch to the My Stores section
- Click on the Domains button
- Enter your domain name into the input field (the domain name should be already registered to you):
You can enter several domains at once using the Plus button. Finally, click the Update button to save changes.
- In a few minutes, you should receive an email with the DNS settings in your mailbox.
- Change the NS or A records for your domain according to the DNS settings
- Change the Magento Base URL in Magento Backend as described in the How do I change Magento Base URL? article.