In order to enable GD Support in your WHM/CPanel VPS you need to complete the following steps:

1. Login to WHM as root
2. Go to Software -> EasyApache
3. If prompted to upgrade, do so then repeat step 2
4. Begin customizing based on the current provile
5. Proceed through the screens until you get to "Step 5"
6. On "Step 5," click on "Exhaustive Options"
7. Under PHP, check the checkbox for GD
8. Proceed with Build & Compile Process
9. Make sure you wait for the build to complete.