Node version manager in macOS Sierra

                                  It's pretty simple to install node version manager(NVM) in macOS Sierra just run these commands one by one in your iTerm2

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.0/install.sh | bash

1 2	export NVM_DIR="$HOME/.nvm" [ -s "$NVM_DIR/nvm.sh" ] && . "$NVM_DIR/nvm.sh"

After this type nvm into your iTerm2 as shown in the picture below.

and voila thats how you can install nvm in macOS Sierra :D