The Halo: Reach beta is now open to the public. All you'll need to participate is a copy of Halo 3: ODST, an Xbox 360 connected to the Internet, and an Xbox Live Gold subscription.

In order to get started, start up ODST and click the "Play The Beta" option in the main menu. You'll be prompted to download the beta client, which is about 1.15 GB. After you've finished the download, restart ODST and choose "Play The Beta" again from the menu.

As you wait for the beta client to finish downloading, check out the preview video released by Bungie. Hopefully the information within will make your first few matches a little less painful.