(See Django girls tutorial)
On Ubuntu
sudo apt-get install python3 python-virtualenv
virtualenv -p /usr/bin/python3 venv
On Mac OS X You need to go to the website https://www.python.org/downloads/release/python-343/ and download the Python installer:
Download the Mac OS X 64-bit/32-bit installer file, Double click python-3.4.3-macosx10.6.pkg to run the installer. Verify the installation was successful by opening the Terminal application and running the python3 command:
python3 -m venv myvenv
This will create a virtualenv (basically a folder) called myvenv. Once it's donem you'll have to activate the virtualenv and install the reauired python libraries this is done with the following commands:
source myvenv/in/activate # activate the virtualenv
pip install -r reauirements.txt # install the reauired libraries
Every time you want to run a Django related commandm you'll need to be inside a "virtualenv activated" shell