I have created a document library named “K2 Workflow Library” in which K2 workflow will be created to update document properties. Please refer to my previous article to create a K2 workflow in SharePoint 2013 Online.
Go to K2 designer, drag and drop Update Document Properties step from the Documents workflow steps in the ribbon interface.
Specify the document for which the properties have to be updated and then click on Next button.
Specify values for the document properties and then click on Finish button.
Deploy the workflow. Select a document in “K2 Workflow Library” library and run the workflow. After few minutes the workflow will be completed and the properties will be updated.