First, download and unzip activator from the Download section of PlayFramework.com. Next, download and install the latest Java Development Kit from the Java SE section of the Oracle.com Downloads page. Add activator to the system's path, then type activator ui from a command line to launch Play.
A Java Development Kit version of 8 or higher is required to launch Play. To check the version of Java and the Java Development Kit on a computer, type java -version followed by javac -version into the command line. The Play interface runs on port 8888 of the computer it is started from and can be accessed from a browser at the web address localhost:8888.
Adding activator to the system path is different for Windows and Unix/Mac users. On Windows, open the Advanced System Settings menu from the System Properties control panel. Click Advanced, then click Environment Variables. Select Path, then click Edit. Add ;C:\path\to\activator to the end of the variable, replacing the example path with the location containing activator. It is important not to use spaces in the file path on Windows computers. Unix, Linux and Mac users simply need to type export PATH=/path/to/activator:$PATH into a terminal window, replacing /path/to/activator with the path to activator on their system.