Client

sudo apt-get update
sudo apt-get install -y apt-transport-https
curl -s https://packages.cloud.google.com/apt/doc/apt-key.gpg | sudo apt-key add -
echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee -a /etc/apt/sources.list.d/kubernetes.list
sudo apt-get update
sudo apt-get install -y kubectl kubeadm

Bash completion

kubectl completion bash | sudo tee /etc/bash_completion.d/kubectl

Manual installation

curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl
chmod +x ./kubectl
sudo mv ./kubectl /usr/local/bin/kubectl

Test

kubectl get nodes -o wide
kubectl get all --insecure-skip-tls-verify

kubectl-commands
https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands

Links
https://kubernetes.io/docs/tasks/tools/install-kubectl/
https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm-init/