Before you dive in...

OpenEnergyMonitor modules are based on the Arduino platform, documentation and application guides assume familiarity with Arduino. If you're new to Arduino, see the getting started guide at the top of the building blocks page. 

Software and firmware examples are stored on GitHub, in order to access and easily stay up-to-date, familiarity with the basics of GitHub will make things easier for you, have a look at: A gentle guide to Git and GitHub as a good introductory guide (written for the Raspberry Pi but the same applies to Linux and OpenEnergyMonitor GitHub repositories)