The ExAM application can be found on the Salesforce AppExchange here. On this page, you are able to view some information about the product as well as a demo. You will log in using your Salesforce credentials from the Org you intend to install ExAM in.
Now that you are logged in you will click Get it Now.
You will then be prompted to choose what type of Org you are installing ExAM into. Just as Salesforce recommends we agree you should test in a sandbox before installing into your production Org. You will click Install in Sandbox.
After agreeing to the Terms and Condition, click Confirm Install.
You will then choose who to install this package for and click Install. We recommend that you choose to Install for Admins Only.
You will need to allow the app to have third-party access so you will check the box Yes, grant access to these third-party websites and click Continue. The app will take several minutes to install and you will receive an Email when it is complete.
You have now successfully installed ExAM into your Salesforce Org