Email subscribers plugin have subscription box and it allows users to publicly subscribe by submitting their email address. You can add subscriptions box to your sidebar (using widget). posts (using short code) and theme file (using PHP code). If you wants to add group selection in the subscription box, please use my Advanced Form add-on plugin.
Widget
To add Subscriptions Box widget to your sidebar, go to your Dashboard. and then click on Widgets menu. You will see a widget called Email subscribers. Click Add Widget button or drag it to the sidebar on the right.
Short Code
This can be used in any page or post within your blog. When your blog encounters text formatted in this style and recognizes it as a subscription box.
[email-subscribers namefield="YES" desc="" group="Public"]
PHP Code
Copy and past the below mentioned php code to your desired template location (i.e in theme PHP file).
<?php es_subbox( $namefield = "YES", $desc = "", $group = "" ); ?>
How it looks in the front end?
Live email subscription box demo available in this website. Please click here to view the demo. When visitors submit their email address, in a few minutes they will get a confirmation email. If they click confirmation link in the email, they will receive a welcome mail for successfully subscription.
Advanced subscription box
If you wants to add group selection in the subscription box, please use Advanced Subscription Box Form add-on plugin.
http://www.gopiplus.com/work/2015/09/24/email-subscribers-advanced-form-wordpress-plugin/
Video Tutorial
http://www.gopiplus.com/work/2014/05/06/email-subscribers-wordpress-plugin-video-tutorial/
Download Link
http://www.gopiplus.com/work/2014/05/06/email-subscribers-wordpress-plugin-download-link/
Official Page with Live Demo
http://www.gopiplus.com/work/2014/05/02/email-subscribers-wordpress-plugin/