Download and compile gh-deployer using go get maunium.net/go/gh-deployer
Configure and start up gh-deployer (example config). The default config path is /etc/gh-deployer/config.yaml.
Configure Github webhooks according to your gh-deployer config.
Create .gh-deployer.yaml in the root of the repository to deploy (example deploy config). If you have gh-deployer started and Github webhooks set up, the server should run the commands as soon as you push the deploy config.