Guide to using Flask-Migrate with Flask-SQLAlchemy to manage schema changes: install packages via pip, configure SQLALCHEMY_DATABASE_URI, init SQLAlchemy and Migrate, define a User model, create the initial DB, then evolve it (e.g., add a role column) and apply updates using 'flask db migrate' and 'flask db upgrade', keeping your database in sync with app changes and reducing manual, error-prone migrations.