Shopify Powered Website Cleanup

I have a very small business and website. www.wonderbub.com The website is slow - images not loading quickly. I want to remove unused files, check for broken links, remove unsued apps and code. I expect this will take approximately 1 hour and I would like to observe/learn via screen share. The website is very basic and this should be a straight forward task. Opportunity for someone to look at SEO after the tidy up.