Install the Yahoo! Messenger for Windows CE on your Palm-size PDA and open Yahoo! Messenger from the start menu. Log in with your Yahoo! ID. If you already use Yahoo! Messenger, you will see your buddy list. If this is your first time using Yahoo! Messenger, click on the \"Menu\" in the upper left corner, click on \"Messenger,\" then click on \"Add a Friend.\" Type in a friend's Yahoo! ID. If they have Yahoo! Messenger, click on their name and send them an instant message!