app/views/devise/registrations/new.html.erb
<div class="devise">
<h3 class="heading">Register an Account</h3>
<%= form_for(resource, :as => resource_name, :url => registration_path(resource_name)) do |f| %>
<%= devise_error_messages! %>
<div class="form-group">
<%= label_tag :first_name, "First Name", :class => "control-label" %>
<%= f.text_field :first_name, :class => "form-control", :placeholder => 'John' %>
</div>
<div class="form-group">
<%= label_tag :last_name, "Last Name", :class => "control-label" %>
<%= f.text_field :last_name, :class => "form-control", :placeholder => 'Smith' %>
</div>
<div class="form-group">
<%= label_tag :email, "Email", :class => "control-label" %>
<%= f.email_field :email, :class => "form-control", :placeholder => 'jsmith@example.com' %>
</div>
<div class="form-group">
<%= label_tag :password, "Username", :class => "control-label" %>
<%= f.text_field :username, :class => "form-control", :placeholder => 'jsmith' %>
</div>
<div class="form-group">
<%= label_tag :password, "Password", :class => "control-label" %>
<%= f.password_field :password, :class => "form-control", :placeholder => 'Something Memorable!' %>
</div>
<div class="form-group">
<%= label_tag :password, "Password Confirmation", :class => "control-label" %>
<%= f.password_field :password_confirmation, :class => "form-control", :placeholder => 'Something Memorable!' %>
</div>
<p><%= f.submit "Register", :class => "btn btn-primary" %></p>
<% end %>
<p><%= render :partial => "devise/shared/links" %></p>
</div>