Log in to the HTML5 client.
Select the Ideas Center workspace, Ideas Grid.
Click in the Workflow State Vote cell of the Idea you wish to submit to display the pick list, then select the Submitted option.
OR
Click on the Open button available on the right-hand side of the Idea Name to open the Idea Card, then click on the Workflow State Vote to display the pick list and select the Submitted option.
The status of the Idea is set to Submitted.