Type the name of the party (bidder or associated owner) in the "Bidder" text field and press ENTER on the keyboard. A separate form, "Party Selection List" should appear. Click on your desired party, then press [OK]. Once back in the "Get Party" form, press [OK] again and your party will be added.
If needed: once you have selected a party using the "Bidder" text field, you can edit that party's information by pressing the [Edit] button. This will open the "Party Form."
For example, you can change the party's: