Clone the repo using git clone https://github.com/orchard0/juice.git or simply download the folder.
Get the Octopus Energy API key here. It is something like sk_live_rvcndtwguaeohpfqbsk12345.
Get the Octopus account number, it can be found, when logged in, under your name on the Octopus account page. It is something like A-1A2B3C4D.
If you have gas then run create_ldz.py using python3 create_ldz.py. This will create a gas local distribution zone lookup table so gas bills can be calculated.