resizing a JPanel inside a CardLayout inside a BorderLayout to the size of the Layout pane

public class DBsetup extends JPanel implements  ActionListener{
public DBsetup(){
		super();
		setLayout(new BorderLayout());
                setSize(500,500);
		next.addActionListener(this);
                next.setSize(20,20);
		previous.addActionListener(this);
                previous.setSize(20, 20);
                previous.setEnabled(false);
		cancel.addActionListener(this);
                cancel.setSize(20, 20);
		
                JPanel buttonPanel = new JPanel();
                buttonPanel.add(previous);
		buttonPanel.add(cancel);                
                buttonPanel.add(next);
		add(buttonPanel, BorderLayout.SOUTH);        
                
                JPanel mainPanel = new JPanel(new CardLayout());
                mainPanel.add(card1(),"card1");
                add(mainPanel,BorderLayout.CENTER);
      
		}
 
	public void actionPerformed(ActionEvent e){}
	
	private JPanel card1(){
		JPanel card = new JPanel();
		//card.setSize(240,120);
		JTextArea welcomeText = new JTextArea("Welcome to the Noteworthy setup wizard! \n\n This wizard will walk you through the " +
				"steps of setting up a new database for your notes, selecting the fields you would like, and running Noteworthy" +
				"for the first time. \n\n\n To preceed press \"Next\", to cancel the setup and exit the program press \"Cancel\" ");
		card.add(welcomeText);
		return card;
		
	}
}