How can I link to my Custom Pages from my store?

If you edited the Cooper Theme before Custom Pages were added but kept it mostly the same:

Find this part in your Layout HTML file.

 <ul id="buttons">
 <li><a href="{{ pages.contact.url }}" class="contact_us">Contact</a></li>
 <li><a href="{{ pages.faq.url }}" class="faqs">About</a></li>
 <li><a href="{{ store.marketplace_url }}" class="store_profile" target="_blank">Marketplace</a></li>
 </ul>

and replace it with this

<ul id="buttons">
{% for page in pages.all %}
<li><a href="{{ page.url }}" class="{{ page.permalink }}">{{ page.name }}</a></li>
{% endfor %}
<li><a href="{{ store.marketplace_url }}" class="store_profile" target="_blank">Marketplace</a></li>
</ul>

If you are building a theme from scratch the only part you need is this. Put it in your Layout file wherever you want it to go.

<ul>
{% for page in pages.all %}
<li><a href="{{ page.url }}" class="{{ page.permalink }}">{{ page.name }}</a></li>
{% endfor %}
</ul>