I’m going to describe this fairly succinctly so you can get up and running in as little time as possible. That being said you will probably need a small dose of luck as I’ve not experienced the same install of an IBM product the same way twice.

I also did the initial install on a VM using VMWare which came in handy as I had to nuke the VM a couple times getting over some hurdles. Additionally I did almost if not all the work from the Linux command line/Bash as root user.

I installed CentOS 6 64bit on my Mac as a VM (with GNOME). I previously had downloaded the various parts and pieces that make up the WebSphere 7 installer and manually combined them together from the ZIP’s and TAR’s provided (yes the parts came in two different compression formats). I downloaded this from the IBM PartnerWorld site so your experience may vary depending on where you get the software.