Once you sign up for an account, you'll need to activate it through an email VMware sends you; then you can download a free 30-day trial. (A full version of VMware Fusion is a reasonable $50.) Open the disk image and do the old drag to install.
Launch the application, and you'll be asked if you want to submit anonymous data and statistics. Your online VMware account will include a trial license key which you'll need to supply; then, click OK and you'll be taken to the application's Virtual Machine Library. Click Create New. VMware will ask you what kind of disk you'll be installing from. In my instance, I was using Remote Disk from a MacBook Air, so I clicked "Continue without disc" and then navigated to the disc, which was being shared from an iMac eight feet away.
VMware will recognize your operating system as Windows but suggest that it's XP; you'll want to change that option to the closest available, which Windows 7 as of this writing. Also, as VMware defaults to allocating 1GB of RAM to the VM, I changed that to 2GB, the Windows 8 recommended minimum. Select Customize Settings, and VMware will prompt you first to save the file. Then click on Processors and Memory and increase the amount of RAM to 2GB.
Close the Settings window and your virtual machine shows a movie-like start arrow. Click it and you're in business. Unlike with Parallels, you'll need to supply the Windows activation code when prompted, as with a standard Windows installation process.
If you don't want to pay to try Windows 8 and, for whatever reason, you don't want to use Boot Camp, you can use VirtualBox, Oracle's free virtualization software.
Download and install VirtualBox from its website. Once that's done, launch VirtualBox and click New to make a new virtual machine. Provide a name for the environment and select Microsoft Windows as the operating system and "Windows 8 (64 bit)" (or just "Windows 8" if you downloaded the 32-bit version) as the version. Then select the base amount of RAM to allocate, I'd say at least 1GB if you're running the 32-bit version and 2GB if you're running the 64-bit version.
Next, you need to create a virtual hard disk. Using the defaults of "Start-up Disk" and "create new hard disk," click Continue and select the format of the disk. I chose a VirtualBox disk, but there are several other formats including Parallels. Click Continue and select whether you want the space to be dynamically allocated or static. Click Continue again and give the disk a name and a maximum size. Click Continue to review your disk settings and click Create. Finally, click Create one more time to tie it all together.
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