--snip--
You now have me worried! I have 3 paper wallets for different coins. I did not go through all those steps with a clean, offline pc
Well, the clean, offline clean PC and rebooting it afterwards is to make sure that:
- nobody is able to see your screen... For example, if you're using a corporate PC, things like VNC can be installed and somebody can be looking at your screen without your knowledge
- no trojan/virus/spyware/... potentially running in the background is able to send data to an attacker (data including screencaps, content of the clipboard, wallet files,...
- rebooting is because you want to make sure your private key, seed or passphrase are defenatly no longer stored in your PC's/printer's memory
So, yeah, i'd defenatly recommand running a paper wallet generator on an offline PC. The odds of exposing your private keys are very small, even if you're running on an online machine, but the purpose of a paper wallet is to store a lot of value for a long time in a very secure manner.
So, if you generate a paper wallet without all the necessary precautions, imho you could have just used a desktop wallet... Much easyer to spend funds, new addresses for every transaction, change addresses, added functionality like the ability to sign messages without having to mess with the private key,...
Basically, as soon as your private key touches an online machine, it's no longer to be considered "as safe as humanly possible". The odds of it being compromised are small, but they still exist.
If you don't store a lot of value on those paper keys of yours, i wouldn't worry to much. If you store a significant amount of value, you can always generate a new paper wallet following the proper procedure, then sweep your old wallet and use the funds to fund the properly generated wallet... no biggie...
