Properly how?
If you're installing an operating system:
* Use trusted-clean binaries to install it with. Eg. a vendor CD, and known clean installation packages.
* Do not connect to an untrusted network or the Internet until the OS is fully configured and patched up-to-date!
I have written some install guides:
http://www.legolas.com/wac/installguides.htmlPS - this thread reminds me of a bonehead MCSE guy at a company I previously worked at. He was installing Windows 2000 on a load of servers, and hadn't even spotted that each one had been compromised by the nimda work while he was installing it. I had to point it out to him.