How do you install custom color schemes in PhpStorm 2016.1 on Mac OSX?
Previous versions you'd place an xml file in a directory like ~/user/webide900/colors and PhpStorm would pick it up and make it an option for you in the settings to switch to one of those themes.
This site where I used to get themes appears to still be up to date but their instructions for install are for old versions.
PhpStorm docs don't make any mention of installing custom scheme files.
To install a custom color scheme you need to create a folder named colors in ~/Library/Preferences/PhpStorm2016.1/. In here you drop the .icls file. Hope this helps.