Top 12 Search Engine Optimization (SEO) Thinks Very important top 12 Search Engine Optimization (SEO) Thinks. 1. Content Writing. 2. Robot.txt. 3. XML Sitemap. 4. Mobile-Friendly. 5.Use 1 H1 tag. 6. Google Search Console. 7.Google Analysis. 8. Domain authority & Page authority. 9.Redirect links. 10.SSL Certificate. 11.Back-links. 12. Brand Signal.