_form.html.erb

<div class="col-md-8 col-md-offset-1">
  <div class="panel panel-default">
    <%= form_for(@weekly_performance_review) do |f| %>
      <% if @weekly_performance_review.errors.any? %>
        <div id="error_explanation">
          <h2><%= pluralize(@weekly_performance_review.errors.count, "error") %> prohibited this weekly_performance_review from being saved:</h2>

          <ul>
          <% @weekly_performance_review.errors.full_messages.each do |message| %>
            <li><%= message %></li>
          <% end %>
          </ul>
        </div>
      <% end %>
      <div class="panel panel-body">
        <div class="field">
          <%= f.collection_select(:user_id, current_admin.users.all, :id, :name) %>
        </div>
        <hr>
        <div class="row">
          <div class="field">
            <%= f.label :Date %>
            <%= f.datetime_select(:week_start, order: [:day, :year, :month]) %>
          </div>
      </div>
      <hr>
      <div class="job_queues">
        <div>
          <%= f.fields_for :job_queues do |job_queue| %>
            <%= render 'job_queue_fields', f: job_queue %>
          <% end %>
        </div>
        <div class="links">
          <%= link_to_add_association 'New Queue', f, :job_queues, class: "btn btn-primary add-button" %>
        </div>
      </div>
      <div class="coaching_forms">

        <h2>Coaching Sessions</h2>

          <%= f.fields_for :coaching_forms do |coaching_form, index| %>
          <div class="panel-group" id="accordion" role="tablist" aria-multiselectable="true">
            <div class="panel panel-default">
              <div class="panel-heading" role="tab" id="headingOne">
                <h4 class="panel-title">
                  <a role="button" data-toggle="collapse" data-parent="#accordion" href="#collapse<%= index.to_s %>" aria-expanded="true" aria-controls="collapseOne">
                    <h4>New coaching form</h4>
                  </a>
                </h4>
              </div>
              <div id="collapse<%= index.to_s %>" class="panel-collapse collapse" role="tabpanel" aria-labelledby="headingOne">
                <div class="panel-body">
                  <div class="coaching_form">
                    <%= render 'coaching_form_fields', f: coaching_form %>
                  </div>
                </div>
              </div>
            </div>
          </div>
          <% end %>
          <br>
          <div class="links">
            <%= link_to_add_association 'New Coaching session', f, :coaching_forms, class: "btn btn-primary add-button" %>
          </div>
          <br>
      <div>
        <br>
      <div class="actions">
        <%= f.submit %>
      </div>
    </div>
    <% end %>
  </div>
</div>

_job_queue.html.erb

<div class="nested-fields">
  <div class="panel panel-body">
    <div class="field">
    </div>
    <hr>
    <div class="row">
      <div>
        <h4 style="text-align: center">Select Job Queue</h4><br>
        <div class="field">
          <%= f.label :project_name %><br>
          <%= f.collection_select(:project_id, Project.order(:project_name), :id, :project_name, include_blank: true) %>
        </div><br>
        <div class="field">
          <%= f.label :job_name %><br>
          <%= f.grouped_collection_select(:job_id, Project.order(:project_name), :jobs,  :project_name, :id, :job_name, include_blank: true) %>
        </div>
      </div>
      <hr>
      <div class="col-md-6">
        <h4 style="text-align: center">Actual score</h4>
        <div class="field">
          <%= f.label :Quality %><br>
          <%= f.number_field :kpi_quality_actual %>
        </div>
        <div class="field">
          <%= f.label :Adherence %><br>
          <%= f.number_field :kpi_adherence_actual %>
        </div>
        <div class="field">
          <%= f.label :Production %><br>
          <%= f.number_field :kpi_production_actual %>
        </div>
      </div>
      <div class="col-md-6">
        <h4 style="text-align: center">Next target score</h4>
        <div class="field">
          <%= f.label :Quality %><br>
          <%= f.number_field :kpi_quality_next_target %>
        </div>
        <div class="field">
          <%= f.label :Adherence %><br>
          <%= f.number_field :kpi_adherence_next_target %>
        </div>
        <div class="field">
          <%= f.label :Production %><br>
          <%= f.number_field :kpi_production_next_target %>
        </div>
        <br>
        <%= link_to_remove_association "Remove Queue", f, class: "form-button btn btn-danger" %>

      </div>

    </div>
  </div>
</div>