SolidWorks will not run on the Mac operating system. You will need to install Windows.
I have my Macbook Air bootcamped with a Windows 7 install. This lets me install SolidWorks on the Windows partition.
I use SW2013 on my MacBook pro using parellells desktop to run windows 7 or 8 as a virtual machine (VM) without any problems. There are a few differences in keyboard shortcuts that I struggle with occasioanly, but that is down to the fact I use SW in a native windows environment all day long at work.
Either the bolotcamp or Virtual Machine (VM) will work well, however in my experience, if you are using the VM option you will need to ensure sufficient allocation of memory to the windows VM, otherwise SW will be slow and sluggish. I have chosen to upgrade to 16Gb of ram so the Mac OS and VM both have 8Gb, this works very well for me, I prefer the VM route on the mac because it allows me to work with SW in its own window from within the mac OS