app/views/shift_preferences/edit.html.erb
<h1>Editing Shift Preferences for <%= @week_template.name %></h1>
<%= form_for([@week_template, @shift_preference]) do |f| %>
<%= f.error_messages %>
<%= render partial: 'form', locals: {f: f} %>
<p>
<%= f.submit 'Update' %>
</p>
<% end %>
<%= link_to 'Show', template_shift_preference_path(@week_template) %> |
<%= link_to 'Back', template_shift_preferences_path(@week_template) %>