There are 2 ways:

The first way...
In your Autoremarketers site, go to the Account & System Management Section, and scroll down to 'Run Administrative Tasks'.

Select > Setup Demo Accounts & Inventory
Password: Demo

The second way...
Go to C:\Program Files\AWG Remarketing\LiveAuction AdminConsole and open/edit AdminConsole.exe.config in a text editor (Notepad is fine). 

Go to around the 15th line and edit it by adding |DEMO after your auction name in the line so it should go from
      <marketplace-list>Your Auction Name</marketplace-list>
      <marketplace-list>Your Auction Name|DEMO</marketplace-list> 
Then when they log into the Admin Console they will need to choose DEMO from the drop down event list and type in the username of Admin and password of 805805