Do seo for my site - how?

Rough order I'd go in: 1. Search Console set up, sitemap submitted, check what's indexed. 2. Work out the 10-20 searches you actually want to show up for, one main one per page. 3. Fix titles and headings on those pages so they match. 4. Make each page answer that search properly, better than what's ranking now. 5. Link your pages to each other. 6. Then think about getting other sites to mention you. Most people jump straight to 6.