To write a Google review you will need to have a Gmail account and a Google+ account. If you do not have your Google+ account set up, you will be promoted to do so before you write the review.
In order to write a Yelp review you need a Yelp account. You can sign up using your email address. This option is best if you are an active Yelp member.
To write a Facebook review you need to have an active Facebook account.