tap/app/views/orders/_user_list.html.erb

<% users.each do |user| %>
    <div class="thumbnail overview">
      <%= link_to image_tag("http://placekitten.com/g/50/50", class: "img-circle dagschotel"), user %>
      <% if user.avatar.exists? %>
        <%= link_to image_tag(user.avatar , class: "img-circle avatar"), new_user_order_path(user) %>
      <% else %>
        <%= link_to image_tag("http://babeholder.pixoil.com/img/190/190", class: "img-circle user_img"), new_user_order_path(user) %>
      <% end %>

    <%= link_to user.name , new_user_order_path(user), class: "btn btn-info",
      style: get_color_style(user) %>
  </div>
<% end %>