If you'd like to stay in touch with people who visit your portfolio, you can create your own newsletter and add it to your page to enable them joining to your mailing list. Send information on newly added galleries, planned trips and your own photo tips. Note, that this feature is available only for Premium users.
First thing to do is to create Mailchimp account. You can do it here: http://mailchimp.com.
To add your own newsletter to your portfolio, log in to your User Panel and go to 'Settings'.
Now choose 'Site settings' and scroll down to see 'Newsletter' section. Enter here your Mailchimp API.