# get the latest nvm release https://github.com/creationix/nvm/releases
curl https://raw.githubusercontent.com/creationix/nvm/v0.29.0/install.sh | bash

# OR
wget -qO- https://raw.githubusercontent.com/creationix/nvm/v0.29.0/install.sh | bash

# Restart your terminal or run
source ~/.profile

# Install the NodeJS version needed
nvm install 4.1

# update npm
npm install npm -g

curl -sL https://deb.nodesource.com/setup_4.x | sudo bash -
sudo apt-get install -y nodejs

# update npm
npm install npm -g