To perform a paid in or paid out you must first set up a list of reasons. This is done from the store setup menu.
Now simply enter your desired reasons into the Reason field, and click Add. Repeat for each reason you want to add to the list. When you have finished entering data, press the Save Store button to save your changes. Your entered options will come up the next time a paid in or paid out is entered in your system.
To change the reason name, just click the name in the list. Type in the new name, and click somewhere else. Click Yes to confirm the change.