After cloning the package from Github, you should run "make" to get all the dependencies and compile the code. Rebar should work as well.
Make sure to check out the README file and setup your AWS credentials so they can be found.
To get everything started in the shell, you need to tell Erlang where to find the beam files:
MBP:/home/code/erlcloud$ erl -pa ./ebin -pa ./deps/jsx/ebin
Then once in the shell:
I'm guessing there is any easier to get all this started but I'm still learning.