1. To install the code manually, first navigate to your Shopify admin and click Online Store.
  2. Next, go to the Actions dropdown and select Edit Code.
  3. Open the theme.liquid file and paste in the following code. Now the size chart button should show up in your product templates.

<link rel=”stylesheet” href=”https://size-charts-relentless.herokuapp.com/css/size-charts-relentless.css” /><br />
<script><br />
var sizeChartsRelentless = {};</p>
<p>sizeChartsRelentless.product = {{product | json}};</p>
<p>{% if product.collections %}<br />
sizeChartsRelentless.productCollections = {{product.collections | json}};<br />
{% endif %}</p>
<p>{% if shop.metafields.sizechartsrelentless.size_charts %}<br />
sizeChartsRelentless.charts = {{shop.metafields.sizechartsrelentless.size_charts}};<br />
{% endif %}<br />