Click To Do on the left-hand side menu. Flows requiring your attention will be listed.
Select the flow you want to work on. This will open the flow and allow you to work on the current step. The current step is displayed on the right of the screen. Completed steps are shown on the left.
Fill in the required information and click Submit. The flow will then automatically proceed to the next step. Ongoing progress of the flow can be monitored in the Flows I'm In view.