The Picn*x Wiki is set up so that it's publicly readable without signing up.
If you wish to modify a page, you do need to sign up. Here are the steps to take...
If you're not already on one of the Linux Picnic's mail lists, you'll need to sign up. This isn't a marketing thing - it's so that anyone involved can see relevant announcement, and so that our "Slauth" authentication software can handle web self-registration based on mail list subscribers. (Currently there is only one list. But we've been talking about making more.)
linuxpicnic - Linux Picnic organizers/volunteers discussion
Once you have your mail list subscription, self-register for web access. Use exactly the same e-mail address as you subscribed to the mail list. You may enter your mail list password - but that's optional - it will mail you a confirmation link and assign a random password if you omit it.