When trying to access the Blueprint API v2, how do you pass the authentication token when trying a getUrl/PostUrl?

For example:

 blueprint_response = getUrl("https://www.zohoapis.com/crm/v2/Deals/" + opportunity_id.toLong() + "/actions/blueprint/");

I need to access and change the Stage value in Opportunities, but I can't because it is not available to do so in Deluge. So I have to do it via the API, but I'm not sure of the proper syntax to access the Blueprint.