Not using an installer
Many experienced Python developers prefer to handle installing packages on their own. If you don't like pip you can get the latest tarballs from http://pypi.python.org/pypi/tiddlyweb and http://pypi.python.org/pypi/tiddlywebwiki and process setup.py
in whatever way you deem reasonable.
Install or run from source
TiddlyWeb can be run directly from a checkout of its code from the source repository:
git clone git://github.com/tiddlyweb/tiddlyweb.git
cd tiddlyweb
(or a clone of your own fork, if you work that way)
Read the README
file you will find there to see the other modules you need to install.
Once you have TiddlyWeb installed you can carry on to Using TiddlyWeb.