If you enable “Minify” option with “auto” mode in W3 Total Cache plugin, it minfies and combines the JavaScript, CSS files and adds the combined javascript file in “<head>” tag.
To improve the wordPress page load time, you need to move the minifed Javascript to footer (after “</head” tag).This can be achieved by adding below tag just before “</body>” in your template.
<!-- W3TC-include-js-head -->
Note: You need to empy all caches after adding this tag to footer.
For example:
<div id="footer" class="clearfix"> <div class="wrap"> </div><!-- .wrap --> </div><!-- #footer --> </div><!-- #container --> <!-- W3TC-include-js-head --> </body> </html>
Note: Combined javascript file is added at tag “<!– W3TC-include-js-head –>”
Reference :https://github.com/crowdfavorite-mirrors/wp-w3-total-cache