How to display Newsletter form in Footer

1. Go to app/design/frontend/default/your_theme/layout/ open newsletter.xml you will see code block like this :

...
<default>

    <!-- Mage_Newsletter -->
    <reference name="left">
         <block type="newsletter/subscribe" name="left.newsletter" template="newsletter/subscribe.phtml"/>
     </reference>

 </default>
...

2. Add following code there like this :

...
<default>
    
    <!-- Mage_Newsletter -->
    <reference name="footer">
         <block type="newsletter/subscribe" name="footer.newsletter" template="newsletter/subscribe.phtml"/>
     </reference>
     
 </default>
...

3. Now Go to app/design/frontend/default/your_theme/template/page/html/ and open footer.phtml then add the following code :

<?php echo $this->getChildHtml('footer.newsletter'); ?>

4. Done.

Add Newsletter subscriber form in header

5. Repeat step 1 to open newsletter.xml file.

6 . Add following code there like this :

...
<default>
    
    <!-- Mage_Newsletter -->
    <reference name="header">
         <block type="newsletter/subscribe" name="header.newsletter" template="newsletter/subscribe.phtml"/>
     </reference>
     
 </default>
...

7. Now Go to app/design/frontend/default/your_theme/template/page/html/ and open header.phtml then add the following code :

<?php echo $this->getChildHtml('header.newsletter'); ?>

8. Done.

OR

Add newsletter form using direct call in any block

Just copy and paste the following code in any .phtml extention file.

<?php echo $this->getLayout()->createBlock('newsletter/subscribe')->setTemplate('newsletter/subscribe.phtml')->toHtml(); ?>