These all seem like good suggestions, especially smart computing and not doing irresponsible things. But you didn't mention the best suggestion of all--use an operating system that doesn't beg to be infected. That is, don't use Windows. There are lots of enjoyable "distros" of Linux, many of which have been very friendly to novices for years. You can compare and check them out at DistroWatch. And of course Linux isn't alone. There's FreeBSD and it's distros, MacOS and maybe even Solaris.