Second: Whatever you do, don't use your private keys on a system that you don't have direct physical control over. You have no way of guessing what could happen, or who could gain control over your private keys and impersonate you.
Third: If at all possible, make certain that your computer is disconnected
from any networks when using your private keys. Also, keep your private
keys on diskette only, and only leave that diskette in the drive when using
your private keys. This helps to improve your security incredibly.