Setting up and using Python3 Virtualenv

Python3 Virtualenv Setup

To install virtualenv via pip
$ pip3 install virtualenv

Note that virtualenv installs to the python3 directory. For me it's:
$ /usr/local/share/python3/virtualenv

Create a virtualenvs directory to store all virtual environments
$ mkdir somewhere/virtualenvs

Make a new virtual environment with no packages
$ virtualenv somewhere/virtualenvs/<project-name> --no-site-packages

To use the virtual environment
$ cd somewhere/virtualenvs/<project-name>/bin
$ source activate

You are now using the virtual environment for <project-name>. To stop:
$ deactivate