I suppose Node and NPM are installed run (if U didn't alredy)
npm install -g ionic cordova
for more installation reference see Ionic docs
clone repository and run
npm install
plug device (with developer settings turned on) and run (e.g. for android):
ionic platform add android
then
ionic run android --device
--device means that emulator will be skipped and app will be deployed to device
for actual development better use:
ionic serve
but this won't work for perfectly for now since FCM requires cordova plugin. (Mocks for browsers will be added if needed)