Sometimes I get really excited about useful tools and articles and I forget to speak in layman's terms when I post about them, so here goes:
SEO means Search Engine Optimization.
It sounds complicated but it's really not. Basically it means making your website look attractive to Google (which is a search engine). If Google likes your site, you show up higher in their search results. That means more people can find your site and in theory, more people click through to your site. That means more traffic, and more traffic means more sales (usually).
That article from Shopify's blog basically gives you 10 steps you can perform yourself to make sure that your website or shop is complete and functioning properly on the internet.
Here are the 10 items it covers:
Meta Tag Audit
Website Content Audit
Google+ page Audit
Online Reputation Audit
Site Speed Audit
Local Schema Audit
Google Analytics Implementation Audit
Follow the instructions, they are pretty straightforward. No need to hire someone to do this. After you finish the items that are relevant to your business, you will be in better shape on the internet. You're welcome.