Having done it on Oracle’s VirtualBox (which is open source and free), here’s it done using VMware Player (which is closed source, but still free for non-commercial use). This is a useful way to create a lab environment on the cheap.
1. Download and install VMware Player, taking all the defaults. https://my.vmware.com/web/vmware/free#desktop_end_user_computing/vmware_player/5_0
2. Download ESXi 5.1.0 (with 60 day eval license). https://my.vmware.com/web/vmware/evalcenter?p=free-esxi5&lp=default
4. Once booted, ESXi installs. Note that it does not generate the warning “Hardware Virtualization is not a feature of the CPU” which you would get if installing within VirtualBox (see pic). After install, disconnect the CD drive.
7. Install vSphere client (more info at http://wp.me/p1EVa3-2Q), point it at the ESXi IP address. Ignore security warnings.
8. vSphere gives Summary view below.