In the Social Room only you will see OPTIONS to start a table with your own selected table name and, optionally, with a password.
Press Options (top left in the Social Room table view)
A Table Name is required
A Password is Optional
Once the password is set, inform the other 3 players.
After having pressed REFRESH, the other 3 players see the table with a padlock
Select a seat, enter the password to join the table.