See my blog posts about setting up the environment:

https://www.rosamund.dev/posts/wagtail-digital-ocean-pt-1

https://www.rosamund.dev/posts/wagtail-digital-ocean-pt-2

If you clone this project, you'll have to change the settings path in manage.py and wsgi.py to: mysite.settings.dev_example

If you don't set up a PostgreSQL one as shown in the Digital Ocean tutorial, you will also have to change the database to a sqlite3 one in base.py:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
    }
}

Generate said database by running python manage.py migrate, then python manage.py createsuperuser so that you can log into the admin of your new site. (Then python manage.py migrate again for the change to take.)

Don't forget to set DEBUG=True in development and add localhost to ALLOWED_HOSTS so you can actually see stuff as you're developing!