1.) Make sure your Elixir environment is at least 1.6.1
elixir -v
2.) Make sure your node version is above 8.5.0
node --version
3.) Get dependencies
mix deps.get
4.) npm install
cd assets
npm install
npm install webpack-dev-server -g
5.) Copy the .env.sample to .env and fill out the values
cp .env.sample .env
6.) Start the development server
mix phx.server
7.) Navigate to localhost:4000