Open a new browser tab and log in to your WordPress.com profile at developer.wordpress.com by clicking the My Apps entry in the top menu of developers.wordpress.com.
Click the Create New Application button.
Enter a Name, Description, and Website URL of your choice.
Enter https://www.socialoomph.com/wordpresscom/callback/ in the Redirect URLs field.
Answer the What is... question, and ensure that Web is selected in the Type radio button.
Click the Create button.
Click your application name in the top My Applications breadcrumb links.