- 
In the upper-right corner of any page, click your profile photo, then click Settings.

 - 
In the left sidebar under Organization settings, click the name of your organization.

 - 
In the left sidebar under Developer settings, click OAuth applications.

 - 
Click Register a new application.
 - 
Under Application name, type "Jira".
 - 
Under Homepage URL, type the full URL to your Jira instance.
 - 
Under Authorization callback URL, type the full URL to your Jira instance.
 - 
Click Register application.

 - 
Under Organization owned applications, note the "Client ID" and "Client Secret" values.

 - 
Link your GitHub account with Jira. For more information, see Atlassian's help documentation.
 
Further reading
- "Integrating Jira with your personal projects"
 - Connect Jira Cloud to GitHub (Atlassian documentation)