I think that this would be pretty good(*, **) https://99bitcoins.com/bitcoin-wallet/paper-wallet/ and it's the first result Google has returned.
You have to scroll down to part 3. Creating a paper wallet (advanced method, ultra secure)

(*) I think it doesn't mention about rebooting the printer or printing something else afterwards (or both), but on the other hand I didn't hear yet of any malware stealing paper wallets from printer's memory either (it may be too much effort and the results would be weak)
(**) I think it doesn't also mention about wiping that USB stick either, but that is an obvious, common sense move

Disclaimer: while I did use paper wallets, I've never was extreme about their security (not so big funds), so I didn't actually do all the steps myself.