Sometimes the wiki might go for days (or even weeks) without any new material being added; other times there can be a flurry of activity. So how do you keep up-to-date without spending every waking hour trying to spot something new?
The most obvious way is to watch pages that interest you. If you are logged in, then at the top of each article, you should see a "watch" tab: Clicking on this will add the page to your personal watchlist (the legend will change to "unwatch"). Using the "my watchlist" link near the top right of the window will show you which pages you are currently watching. In "my preferences", find the E-mail section of User Profile and make sure that "E-mail me when a page on my watchlist is changed" is checked and save changes if necessary. You will now get an e-mail telling you when one of the pages on your watchlist (or its associated "discussion" page) is modified, and who made the change.
Pros: You only get alerts for pages you've expressed an interest in. Cons: You won't be told about new pages, since you can't be watching them!
For a quick check on everything that's changed recently, you can use the Recent changes page from the navigation menu. The options at the top allow you to select how far back to look and which "NameSpaces" to search (normally you can just leave Namespace set to "all"). This is mainly an administrative tool, used by Sysops to patrol edits.
Pros: You can quickly see all recent changes, along with links to show difference in versions. Cons: Can be cluttered with lots of minor corrections. You can miss an important change in amongst the others. You still have to come looking for changes.
RSS/Atom News Feeds
While you're viewing the Recent changes page, you should see "RSS" and "Atom" links in the "toolbox" at the left of the screen. If you have a news reader/aggregator then you can use these to subscribe to a news feed which will allow you to see when the wiki changes.
Pros: You can monitor the wiki along with all your other news feeds, so don't have to make special visits. Cons: As for Recent Changes.