at least that's what I do. Then I log onto the site and follow the directions. There might be an easier way but I'll leave that for others to tell you how.

Do not link to your hobby email as I did.  I imagine it  could be traced under some circumstances.  

You buy the minutes refill card anywhere with cash.  The tracfone has add minutes in the center button menu on the handset.  You push add minutes, enter the code you scratched the covering off on the card.  Enter the numbers.  Leave the handset on until it shows the minutes have been added.  Throw used refill card in the trash...  no need to take it home.  Shut off phone & hide it again.
H