You legally make an official portable version of Photoshop CS6. However, you can install it on an external drive with a valid license:
In a digital landscape where software lived on heavy spinning disks, a legend whispered through the forums of 2012: the "Ghost of CS6." adobe photoshop portable cs6 131 x32 x64 multi rar new
The Adobe Photoshop Portable CS6 13.1 x32 x64 Multi RAR has the following system requirements: You legally make an official portable version of
of the Adobe Photoshop CS6 software. While genuine versions of Creative Suite 6 exist, Adobe does not offer a "portable" edition that runs from a USB drive without installation. Photoshop "portable" is a well known hack
Photoshop "portable" is a well known hack. It's pirated and illegal, end of story. This isn't the first time we've heard about it. Adobe photoshop CS6 extended portable - | Community