drupal 7 SSL a lot of insecure urls
One solution, if you're wanting to force your site to always to use SSL, is to do it at the Apache level by adding this to your .htaccess:

RewriteCond %{HTTPS} off
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]


That's probably the quickest way. The best way is subjective; your needs might be different depending on priorities (e.g. for performance reasons you might want to force many static pages to HTTP).