Manifest files contain metadata that describes all development objects required for a specific application that you develop in Workflow Studio.
Add Workflow Studio items
In Workflow Studio, open the Deployment pane by selecting either Deployment Services from the Common ribbon or Deploy from the Build ribbon.
Click the Open Manifest button located above the Build Order pane.
Search for and select the manifest file you need to update.
You should see the manifest tree open.
Right-click in the white space of the Manifest Tree pane and select Add to Manifest.
This opens the Add to Manifest dialog, which contains a copy of your source control tree.
Expand the tree and select the Workflow Studio items you want to add to your project and then click OK.
You should see the new items added to the manifest.