If you want to update your blog subscribers via email without having to deal with third party sites like Mailchimp or Convertkit (which sometimes come with expensive subscriptions, and endless hours of extra work), then I suggest setting up this simple widget using the handy Jetpack plugin.
Luckily this post is short and sweet! All you need to do is install the Jetpack plugin and add the widget labeled:
Blog Subscriptions (Jetpack)
to your Primary Sidebar. Enter the information, and click save. Now your email subscribers will be updated via email every time you write a new post.