How to Dockerize a lumen based backend app

My website’s back-end developed by lumen 5.8 and it’s separated from front-end and I wanted to deploy my website’s back-end to production server using Docker container, for that I came cross how to dockerize my lumen app and then I studied about using docker functions and advantages.

my server requirements are
Digital-ocean Ubuntu 18.04

So my question is how to dockerize lumen based app ?