Scroll down to ATLASSIAN MARKETPLACE and click on "Find new add-ons"
Search for "STRAD Workflows" and subscribe for a free trial
You can verify the plugin installation from "Manage add-ons" page where STRAD Workflows will be listed as an item along other add-ons that you might have installed.
Finding and configuring STRAD Workflows
Once the STRAD Workflows plugin has been installed on your Confluence instance, it will be easily accessible from the Confluence Administration section. In the left-side menu, you will see a new section called "STRAD Workflows". Click on the "Administration" link below it. This will present to you the administrator configuration page like below.
Once you see this, STRAD Workflows has been successfully installed on your Confluence.