# 01 install postgres, login via system acc, and start psql:
sudo apt install -y postgresql
sudo -i -u postgres
psql

# 02 Edit /etc/postgres/{Version}/main/postgresql.conf and set next:
# listen_addresses = '*'  # by default it's bound to localhost, * allows connect from all addresses
# port = 4312 # security reasons

# 03 Edit /etc/postgres/{Version}/main/pg_hba.conf and set next to the end of the file:
# host    all             all             all                     md5

# 04 restart to apply changes
systemctl restart postgresql