The blog post still mainly works, here are some more links for the service account creation.
Create a new project, by clicking 'CREATE PROJECT': https://console.developers.google.com/cloud-resource-manager
Wait until it's created, refresh the site. Now click on your project, this will take you here (you can see your selected project on the top of the page): https://console.developers.google.com/iam-admin/iam/project
On the left side you will see Service Accounts, go there: https://console.developers.google.com/iam-admin/serviceaccounts/project
Create a service account by clicking on 'Create service account'. Give it your desired name.
You will see your service account, you can then create a key for it by clicking on the dots to the right of it, choose the P12 format.
Now you need to enable the Google Analytics API for your project. To do This go here and press enable: https://console.developers.google.com/apis/library/analytics.googleapis.com