Run! ;o)

No but seriously. First, decide if you want to be a part of the group. Do you like the text of the invitation? Do you know the group's moderator?

If you’re interested, just click Join this group! A page opens describing the group. After reading a bit about it, if you’d like to join, click Join the group. If you prefer to simply receive the emails sent by this group, click join the mailing list instead.

Note: you may be asked to sign in or register for a Yahoo! ID to access all the web features of your group.

Other ways to subscribe: reply to the invitation email with an empty message, or send an email to:

groupname-subscribe@yahoogroups.com

…making sure that you replace "groupname" with the actual name of the group (e.g., pastry_chefs-subscribe@yahoogroups.com).