Pull request labels

In your Account Settings, you can configure ReleaseHub to create environments through the use of Github's Labels.
Access your Account Settings
At the bottom of the Account Info tab in your Account Settings, you will find your Github Settings.
Account Settings for Github
The setting Create Environments by applying labels to Github PR's is automatically turned on and defaults to a label named Create ReleaseHub Environment. If you wish you change the label name, do so, and click the Save button.
In Github you'll need to create a new label that matches what is shown in ReleaseHub. If you're unfamiliar with this process, please refer to Managing Labels in the Github docs.
Adding a Label in Github
Add the Label to the Pull Request and ReleaseHub will create the Environment. If you have turned on Comments, Statuses, or Deployments, ReleaseHub will update the Pull Request with information as your environment is created.