wp-mpdf

1. Upload the whole plugin folder to your /wp-content/plugins/ folder.
2. Set write permission (777) to the plugin dir folder => /wp-content/plugins/wp-mpdf/cache
3. Go to the plugins page and activate the plugin.
4. Add to your template
   php
if( function_exists( 'mpdf_pdfbutton' ) ) {
mpdf_pdfbutton();
}
   or as a small button
   php
if( function_exists( 'mpdf_pdfbutton' ) ) {
mpdf_pdfbutton( false, 'my link', 'my login text' );
}
   The second text specifies the text which should displayed if you have checked “needs login” and a user isn’t logged in. (if you wish to open the pdf print in a new tab you may pass “true” for the first parameter)
5. You can adjust some options: in your admin interface, click on plugins and then on wp-mpdf. For allowing or disabling pdf export you can use the checkbox when creating/editing a post or a page.
6. Place your templates into /wp-content/wp-mpdf-themes

The mpdf_pdfbutton function signature:
php
function mpdf_pdfbutton( $opennewtab = false, $buttontext = '', $logintext = 'Login!', $print_button = true, $nofollow = false, $options = array() )
The options array supports
php
'pdf_lock_image' => '/my/image/path/relative/to/wordpress/route'
and
php
'pdf_image' => '/my/image/path/relative/to/wordpress/route'
to overwrite which icon should be used.