Login into Postgresql

Psql admin

sudo -i -u postgres
psql


CREATE DATABASE "db_name";
CREATE USER "your_user" WITH ENCRYPTED PASSWORD 'XXXXXXXX';
GRANT ALL PRIVILEGES ON DATABASE "db_name" TO "your_user";
GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA public TO "your_user";
GRANT ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA public TO "your_user";
GRANT ALL PRIVILEGES ON ALL FUNCTIONS IN SCHEMA public TO "your_user";
ALTER DATABASE db_name OWNER TO your_user;