Liberapedia is for anyone with a computer and Internet connection, unless you are a conservative and in which case you probably don't fit the beforesaid requirements. If you are a neocon, and you have an "Internets" connection and computer, then STAY AWAY. If you try to vandalize or add nonsense/gibberish, Elassint, Ajuk, Proxima Centauri or Rushwrj13 will send you scurrying back to the foul hole from whence you came.
To begin to contribute constructively, click the "Log In/Create Account" button on the top-right corner of the screen. It is present everywhere on Liberapedia. Click "Create Account" and enter the necessary information. You do not need to enter your email address or real name. Don't put anything irreverent as a username.
You can still contribute if you do not create an account, but your IP address (something like 220.127.116.11) will become like a username.
Once you have logged in (if applicable), you will see either six or three button on the top-right corner of the screen. Your username will be red. To edit it, click it and click the "edit" tab.
Your "my talk" button will also be red. A user will welcome you soon after you create an account or begin to contribute.