Before following below steps, you can run as root user

sudo -s

• INSTALL DOCKER ON LINUX

# Check that HTTPS transport is available to APT
if [ ! -e /usr/lib/apt/methods/https ]; then
    sudo apt-get update
    sudo apt-get install -y apt-transport-https
fi

# Add the repository to your APT sources
sudo sh -c 'echo deb https://get.docker.com/ubuntu docker main > /etc/apt/sources.list.d/docker.list'

# Then import the repository key
sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9

# Install docker
sudo apt-get update
sudo apt-get install -y docker.io cgroup-lite apparmor

• INSTALL ALPINE - A SMALL OS AND POSTGRES -ALPINE VERSION

docker pull alpine
docker run -i -t alpine /bin/sh
docker pull postgres:9.6.2-alpine

• INSTALL PGADMIN 4 ON DOCKER

docker pull fenglc/pgadmin4
# link pgadmin 4 to your docker container of PostgresQL, 
# where test-pgadmin4 is the name for the container of pgadmin 4 and db-test is the name of the PostgresQL container
docker run --name test-pgadmin4 \
--link db-test:postgres \
-p 5050:5050 \
-d fenglc/pgadmin4