It really wasn't bad to do at all. I called SW to walk me thru it and I did fine. You go into the travel tools, then cancel a flight, put in the Confirm Number and your name, it pulls up the flight, you click cancel and there is an option for refund or credit.
The only thing I did wrong was I cancelled, then booked, and had credits left over still. Then I cancelled the second booking and booked a third, Saved $15 each ticket and I put the credit from the second booking for the third tickets.
Now I have credits on the first and second booking for each person!!!!