Use a prepaid phone, pay for it and the minutes in cash. It's possible you'll be on vid when you buy the phone, so do it far away from your neighborhood.
If you chat to her through Yahoo, don't use it for a file transfer because that reveals your IP address.
Install TOR, learn to use it.
Install TrueCrypt and whatever files you have on your PC, encrypt them. Then run a program that overwrites all the blank space on your HD with random data.
Better safe than sorry.
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Old enough to be your daddy
