If you're on windows download the zip, right click on it and select something akin to "extract". This will extract the files into a folder. After the extraction is complete enter the folder and then double click on pound2pounded.exe
This file is the app that actually runs the game.
If when you're in the folder you only see three files called pound2pounded without any .exe at the end it's because you don't have file extensions visible in your settings. In that case either enable file extensions or just try to run the first of the three files (usually they're ordered by name).