This article will guide you how to create an A record in cPanel. Sign into your cPanel and follow these steps:
1. Under the Domains section select Zone Editor
2. To the right of the desired domain, click + A Record
3. You will get a popup, enter in only the beginning of the subdomain, the domain will be autofilled. Enter in the IP Address you want to point the subdomain to.
4. Finally click Add an A Record, you will get a confirmation message like so