Xkcd dating profile
One thing I didn't do, although it's worth considering, is use a stateless operating system like Tails.You can configure Tails with a persistent volume to save your data, but no operating system changes are ever saved.
But every time a file moves back or forth, there's the potential for attack. Stuxnet was a US and Israeli military-grade piece of malware that attacked the Natanz nuclear plant in Iran.
Malware can silently write data to a USB stick, but it can't spin the CD-R up to 1000 rpm without your noticing.
This means that the malware can only write to the disk when you write to the disk.
The less software you install, the less an attacker has available to exploit.
I downloaded and installed Open Office, a PDF reader, a text editor, True Crypt, and Bleach Bit. (No, I don't have any inside knowledge about True Crypt, and there's a lot about it that makes me suspicious.