How to make 2 column 3 posts ?

Hello,

I want to make a slider like this ; http://i.stack.imgur.com/JAfRc.jpg

my html codes ;

<div class="slider">

  <div class="slider-item">

     <div class="col-md-8">
        <article class="post"><!-- post --></article>
     </div>

     <div class="col-md-4">
        <article class="post"><!-- post --></article>
        <article class="post"><!-- post --></article>
     </div>

  </div>

</div>

[closed as duplicate of https://wordpress.org/support/topic/how-to-make-2-column-3-posts-slider-for-wordpress?replies=1 – please start only one topic per question, and continue with your original topic and add more details or information there]