django-admin startproject myproj
cd myproj
python manage.py startapp myapp

from django.db import models
from django.contrib.auth.models import AbstractUser
class User(AbstractUser):
  name = models.CharField(blank=True, max_length=255)

INSTALLED_APPS = [
  ...
  'myapp',
]
AUTH_USER_MODEL = 'myapp.User'

from django.contrib import admin
from django.contrib.auth.admin import UserAdmin
from .models import User
admin.site.register(User, UserAdmin)

python manage.py makemigrations myapp
python manage.py migrate
// python manage.py createsuperuser