It' simple. Just download your favorite penis distribution, and follow these easy steps to install it.

[user@localhost]$ tar -zxf penis-1.0.69.tar.gz
[user@localhost]$ cd penis-1.0.69
[user@localhost]$ ./configure
(configure will print a lot of messages. Ignore them unless they warn of missing components. If you have any problems, make sure you have a recent version of Testicles
[user@localhost]$ make
[user@localhost]$ make install

Note, you may need root access to install a new bodypart. Check with your system administrator about this.
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