Certainly! Newsletter signup forms are a valuable tool for building your email subscriber list and keeping your audience engaged with your content. Here are 21 newsletter signup form examples along with basic steps on how to add them to your website:

1. Simple Inline Form:
This is a basic form integrated directly into your website's content.

How to Add: You can add a simple inline form by embedding an HTML form code in your webpage. You can use a service like MailChimp, ConvertKit, or your email marketing provider to generate the form code.

2. Pop-Up Subscription Form:
A pop-up form that appears when a user visits your site, often triggered by user behavior like time spent on the site or exit intent. https://claspo.io/blog/10-strong-newsletter-signup-examples-and-useful-tips/

How to Add: Many email marketing platforms offer pop-up form integrations. You can customize the appearance, timing, and trigger conditions.

3. Sidebar Widget Form:
A form placed in the sidebar of your website, allowing users to subscribe from any page.

How to Add: If you're using a content management system (CMS) like WordPress, you can add a widget to your sidebar and paste the form code there.

4. Slide-In Form:
A form that slides in from the corner of the screen, typically after a user scrolls a certain distance down the page.

How to Add: Similar to pop-up forms, slide-in forms are often provided by email marketing platforms.

5. Full-Screen Overlay Form:
A form that covers the entire page, requiring users to interact with it before accessing the content.

How to Add: Email marketing platforms may offer overlay forms as part of their features.

6. Exit-Intent Popup:
A pop-up that appears when a user is about to leave your site.

How to Add: Look for email marketing tools or third-party plugins that offer exit-intent popup functionality.

7. Content Upgrade Form:
Offer downloadable content in exchange for email addresses, such as eBooks, whitepapers, or templates.

How to Add: Set up a landing page for the content, and integrate a form that captures email addresses before granting access to the download.

8. Social Media Call-to-Action Form:
Promote your newsletter on social media platforms with a signup form.

How to Add: Share a link to a dedicated landing page or use a link in bio feature to direct users to your signup page.

9. Header or Footer Form:
Include a subscription form in the header or footer of your website for easy access.

How to Add: This can often be done through widgets or plugins in your CMS.