How can I implement a collapsible/responsive sidebar nav in Bootstrap?

Question

I'm using the flatly theme from bootswatch.com

It has a collapsible topnav bar, but I want to refactor it so it's a sidebar nav rather than topnav.

Here is the current code:

Toggle navigation Brand

  <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
    <ul class="nav navbar-nav">
      <li class="active"><a href="#">Link <span class="sr-only">(current)</span></a></li>
      <li><a href="#">Link</a></li>
      <li class="dropdown">
        <a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">Dropdown <span class="caret"></span></a>
        <ul class="dropdown-menu" role="menu">
          <li><a href="#">Action</a></li>
          <li><a href="#">Another action</a></li>
          <li><a href="#">Something else here</a></li>
          <li class="divider"></li>
          <li><a href="#">Separated link</a></li>
          <li class="divider"></li>
          <li><a href="#">One more separated link</a></li>
        </ul>
      </li>
    </ul>
    <form class="navbar-form navbar-left" role="search">
      <div class="form-group">
        <input type="text" class="form-control" placeholder="Search">
      </div>
      <button type="submit" class="btn btn-default">Submit</button>
    </form>
    <ul class="nav navbar-nav navbar-right">
      <li><a href="#">Link</a></li>
    </ul>
  </div>
</div>

I'm hoping I just have to change a few class names to get it to work before I invent my own method. (I'm new to bootstrap).