1. Clone repository
2. cd magento/<version>/dockerfiles 

Find .env file open it with editor and replace all vars wrapped with {{var}} .  
Example: DB_USER: {{DB_USER}} to  DB_USER:magento

3. docker-compose up -d 

version: '2'

volumes:
  mariadb_data:
    driver: local
  magento_data:
    driver: local

services:
  magento:
    image: ${REGISTRY}trydirect:magento:2.3.2
    container_name: magento
    env_file:
      .env
    volumes:
      - ./magento:/home/magento2   
      - /var/www
      - magento_data:/data
      - ./cron:/var/spool/cron/crontabs
    depends_on:
      - mariadb
    working_dir:  /var/www/magento2

  mariadb:
    image: "mariadb:latest"
    container_name: magento_mariadb
    env_file:
      .env
    volumes:
      - "mariadb_data:/var/lib/mysql"

  nginx:
    image: ${REGISTRY}nginx-le:stable
    container_name: nginx
    env_file: .env
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./certs/ssl:/etc/ssl/nginx
      - ./certs/letsencrypt:/etc/letsencrypt
      - ./cron/nginx:/var/spool/cron/crontabs
      - ./nginx/conf.d:/etc/nginx/conf.d/
      - ./nginx/nginx.conf:/etc/nginx/nginx.conf
      - ./null:/etc/nginx/sites-enabled
      - ./supervisord/nginx.conf:/etc/supervisor/conf.d/nginx.conf
    links:
      - magento
    entrypoint: /usr/bin/supervisord -c /etc/supervisor/supervisord.conf -n

volumes:
      - ./magento:/var/www/magento2