HTML

<div class="how_it_works_numbered_list" >
  <ul>
    <li>My item 1</li>
    <li>My item 2</li>
    <li>My item 3</li>
  </ul>
</div>

CSS

.how_it_works_numbered_list ul {
  counter-reset: li;
  list-style-type: none;
  font-size: 14px;
  line-height: 18px;
  padding-left: 10px;
}

.how_it_works_numbered_list ul li {
  position: relative;   
  padding: 10px 0 10px 40px;
}
.how_it_works_numbered_list ul li:before {
  content: counter(li);
  counter-increment: li;
  height: 30px;
  width: 30px;
  border: 2px solid blue;
  border-radius: 50%;
  color: red;
  text-align: center;
  font-size: 20px;
  padding-top: 4px;
  position: absolute;      
  left: 0;
  top: 4px;
}