Turn up with something you are working on ready to talk about it (printouts work better than a laptop).
You should be able to explain the project and target audience and goals so that comments can be relevant to the project.
Once that's done other people in the group will give constructive feedback.
Each person gets 20 minutes focused on them.
Even if you don't have something to talk about you can still come and crit other peoples work.
The crit isn't restricted to UX design. All designers are welcome if you just want to bring along a current project that's unrelated to the web that's fine.
Here are a few dos and don'ts
Do know what you want out of the crit and tell people early on, it could be opinions on the design or opinions on function or UX.
Do be succinct with your description of the project.
Don't bring work that is finished or can't be changed criting this is pointless.
Don't bring something that isn't your own work, that's not fair on the person who did it.
Do make sure what you are saying is relevant.
Do play nicely.
If going to a crit is new to you have a look at this. http://www.scottberkun.com/essays/23-how-to-run-a-design-critique/
Added by gavinwye on July 29, 2008