Add App and obtain the apikey

Go to the My Apps on the Developer Services portal to register apps. You can access the the My Apps page from the main menu of the portal.

To register a new app, select the App a new app button on the My Apps page:

The portal then displays the app registration form: 

Specify app name, callback URL, and select a product from the list. The product is the actual API you want to get access to.

Click Create App button and notice new application entry. Your application now waits for approval by Ryanair administrators.

After a while, when your reqeust gets approved you will see Approved status of your application

Click on your app to expand all application properties

To get access to the product's APIs you need to pass your Consumer Key. Guide on how to do it can be found here.