Edit in JSFiddle

li {
  list-style: none;
     margin:0px 0px 10px 0px;
}
li.sample1:before {
  content: "※";
  color: red;
}
li.sample2:after {
  content: "\00BB";
  color: red;
  padding: 2px 5px;
  margin-left: 5px;
}
li.sample3:before {
  content: "new";
  color: red;
}

<ul>
  <li class="sample1">詳しくは</li>
  <li class="sample2">詳しくはこちら</li>
      <li class="sample3">詳しくはこちら</li>
</ul>