Paste it wherever your site lets you add HTML. On Squarespace, Wix, Shopify and WordPress that is usually a footer or custom code block.
<a href="https://sunshinecoastbusinessguide.com.au/" title="Listed in the Sunshine Coast Business Guide"><img src="https://sunshinecoastbusinessguide.com.au/assets/badge.svg" alt="Listed in the Sunshine Coast Business Guide" width="270" height="48"></a>Prefer text? Link the words you like to https://sunshinecoastbusinessguide.com.au.