app/views/devise/registrations/edit.html.erb
<h2>Edit <%= resource_name.to_s.humanize %></h2>
<%= simple_form_for(resource, as: resource_name, url: registration_path(resource_name), html: { method: :put }) do |f| %>
<%= f.error_notification %>
<div class="form-inputs">
<%= f.input :email, required: true, autofocus: true %>
<% if devise_mapping.confirmable? && resource.pending_reconfirmation? %>
<p>Currently waiting confirmation for: <%= resource.unconfirmed_email %></p>
<% end %>
<%= f.input :password, autocomplete: "off", hint: "leave it blank if you don't want to change it", required: false %>
<%= f.input :password_confirmation, required: false %>
<%= f.input :current_password, hint: "we need your current password to confirm your changes", required: true %>
</div>
<div class="form-group">
<%= f.button :submit, "Update" %>
</div>
<% end %>
<h3>Cancel my account</h3>
<p>Unhappy? <%= link_to "Cancel my account", registration_path(resource_name), data: { confirm: "Are you sure?" }, method: :delete %></p>
<%= link_to "Back", :back %>