Copy default.editordb and name the new folder editordb
Copy default.docker-compose.override.yml and name it docker-compose.override.yml
Go to docker-conf/secrets and copy the files with example before them and name them the same only without example.
Change your secrets in there if you need to.
Go to logs/editor and create 2 files: apache2-access.log and apache2-error.log
Go to logs/front and create 2 files: apache2-access.log and apache2-error.log
Go to logs/photostock and create 2 files: nginx-access.log and nginx-error.log
Go to public_html/editor/sites and copy over the example.sites.php file and name it sites.php
Go to public_html/editor/sites/editor and copy over the default.settings-nl.et1local.inc file and name it settings-nl.et1local.inc
Go to public_html/front/inc/conf and copy over the default.nl_entityone.et1local.inc and name it nl_entityone.et1local.inc
@Todo: explain what to add to /etc/hosts file and which urls/ports to use
Oh yeah, apparently, you should do a git flow init after you did an initial git clone from the gitlab repo.
Just use all the defaults from git flow and you'll be fine!