how to add footer in frappe

<div id="footer-html" class="visible-pdf">
<hr>
        {% if not no_letterhead and footer %}
        <div class="letter-head-footer">
            {{ footer }}
        </div>
        {% endif %}
        <p class="text-center small page-number visible-pdf">
            {{ _("Page {0} of {1}").format('<span class="page"></span>', '<span class="topage"></span>') }}
        </p>
    </div>