See Risum's presentation on Youtube
First of all, it's needed to have Git, Node.js, Yarn and Expo installed on your system. After that, run these commands on your terminal:
# Install Expo Client
npm install -g expo-cli
# Clone the repository
git clone https://github.com/Risum-Corporation/risum.git
# Enter in the project folder
cd risum
# Install the dependencies
yarn
# Start Expo
expo start
Try the app!