The first step is to configure the main settings for comments by clicking Feature Review Settings on the admin menu. This option will only be available if you have Feature Review admin permissions. The following options will be available to configure reviews:
                              

1. Use Feature Reviews – This is the main setting to turn reviews on in your store. No feature review options or other admin links will be viewable until this has been turned on.
2. Approval Required – If this is turned on, reviews will not be posted live to the site until an admin has read and approved them. 
3. Check Reviews – Generally used as an alternative to Approval Required, this setting will flag all new reviews so the admin can still review them, however new reviews will be posted immediately to your site.
4. Who Can Write a Review – This determines what kind of user can write reviews. You can set this to anyone, which allows any visitor to your site to add reviews (generally not recommended unless you have approval required), Registered Users which will allow only logged in users to add reviews, and Verified Users, which will require a login and a verified email address (you generally will want to turn on email verification in your user settings for this. 

 
Click Save Changes to save your settings.