1) Do you have a twitter account?
First things first, as they say. If you have a twitter account, great. If not, go to Twitter, and select "sign up." All you need for a new account is an email address. If you are setting up a new account, go ahead and add just a little bit of biographical info and a picture to your profile. It will help other people know that you are a real person, and not a spammer.
2) Is there a designated hashtag?
A hashtag is a way of organizing conversations on Twitter. Look over your materials for the event - see that number sign (#)? That, along with the letters and/or numbers that come after it, is the hashtag. So, for example, at the Gulf Coast Synod (ELCA) Assembly this year, the hashtag is #TLGCS12 (Like many hashtags, it is a handy abbreviation: Texas-Louisiana Gulf Coast Synod Assembly, 2012). Figure out what hashtag people are using with your event.
3) Follow the conversation
Once you know the hashtag, there are a couple of different ways to follow the conversation:
Search within the Twitter website.
This is the simplest way to follow a hashtag. Go to the "search" bar across the top of the Twitter website. Enter the event hashtag. Click the search button. Ta-da! There is the conversation about your event! Note, you can sort the "tweets" - pieces of the conversaiton - either by popularity (click on "top" at the top of the search results) or chronologically (click on "all" at the top of the search results). This is the easiest way to follow the conversation - but it will not update as frequently as some other methods.
Twubs is a wonderful website for following hashtag conversations. Log into your Twitter account, and then head over to Twubs. Click on "Sign Up" - it will open a new window, and ask to access your twitter information. Click "Ok." In the search bar at the top of the site, enter your hashtag. Twubs will filter all tweets with that hashtag, and will also add the hashtag to all of your tweets so that others can see them. It takes a couple of extra steps, but Twubs has some real advantages over a simple search on the Twitter website.
3rd Party App
Finally, you can use an application to follow the conversation. Two of the most popular are Tweetdeck and Hootsuite. Go to their respective websites, and download the program. Log in, authorize the program to access your Twitter information. From there, you can set up a real-time search for your hashtag, which will be there every time you open up the program. Once again, these applications take a few extra steps, but they are extremely beneficial if you are going to follow a hashtag over an extended period of time. (In my experience, the choice of Tweetdeck or Hootsuite is a matter of personal preference)
4) Jump In
Once you have followed the conversation for a bit, jump right in. What is interesting to you in the event? What is catching your attention? What are others saying that you want to know more about?
Depending on the size of the event and the number of people on twitter, the conversation could move quickly. Don't get overwhelmed - you do not have to read ever single tweet. Just watch for what catches your eye.
And now you are all set. Have fun, enjoy the conversation!
*Note* Mobile use: There are lots of very good mobile apps if you following a twitter conversation on your mobile device. I use Hootsuite and Tweetbot on my mobile devices.