Select a POS publication and click on it.

You now see the briefing items of the campaign that are selected with the POS channel. Click on the 'plus' icon of a briefing item.

Now you can select the 'POS Template' that you want to order.
And then press 'Generate' and the POS item(s) will be generated.

In the work-flow stages you can see the items being generated.

When the generation is finished the POS items you have ordered are in the design stage.

Click on the 'Design' icon in the workflow and you will go to this stage and will see the POS items that are in that stage. Now you can start the design of the items.
Also the bottom of the page you can scroll to the items you want to see and click on them.