How do I get access to a running portal?

In advance, sorry for the newbie question. I have installed SAP NetWeaver Developer Studio, and the SAP PDK, and I'm trying to create a simple portal application in .NET. I am reasonably familiar with .NET and have experience using the .NET Connector.

The first thing it says is that I need access to a running portal. How do I get this? Do I create one somehow? Where can I find out more about creating/accessing portals? From the Server Explorer, I can see where I can set up connections to existing portals, but how do I create a portal with a user and a password so I can connect to it?

Thanks for your time,

Derek