To run twee, you will need a copy of this code, a local Python installation, and a .tw file. You can get this fork from github using, for example, the ZIP button. Python should come pre-installed on a Mac; a Windows installer is available at python.org. You can find some sample twee files at gimcrackd.com.
Once you have all those, open the Terminal or a command prompt, change to the twee directory, and type something like:
./twee my-input-file.tw > my-output-file.html
To compile to Sugarcane instead of Jonah, use the -t flag:
./twee -t sugarcane my-input-file.tw > my-other-output-file.html
The other targets are not recommended.
See the twee documentation for more information about twee.