related_posts.html

<div class="relatedPosts">

<h4>You May Also Like</h4>

{% assign maxRelated = 6 %}
{% assign minCommonTags =  2 %}
{% assign maxRelatedCounter = 0 %}

<ul>
{% for post in site.posts %}

    {% assign sameTagCount = 0 %}
    {% assign commonTags = '' %}

    {% for category in post.categories %}
      {% if post.url != page.url %}
        {% if page.categories contains category %}
          {% assign sameTagCount = sameTagCount | plus: 1 %}
          {% capture tagmarkup %} <span class="label label-default">{{ category }}</span> {% endcapture %}
          {% assign commonTags = commonTags | append: tagmarkup %}
        {% endif %}
      {% endif %}
    {% endfor %}

    {% if sameTagCount >= minCommonTags %}
      <li>
      <p><a href="{{ site.baseurl }}{{ post.url }}">{{ post.title }}</a></p><!-- {{ commonTags }} -->
      </li>
      {% assign maxRelatedCounter = maxRelatedCounter | plus: 1 %}
      {% if maxRelatedCounter >= maxRelated %}
        {% break %}
      {% endif %}
    {% endif %}

  {% endfor %}
</ul>
</div>