What are The Most Common SEO Mistakes? DIY SEO

Most common mistake in SEO are:
Page Meta titles (home for home page, instead of keyword oriented titles)
Example: Home Page
Should stat Los Angeles SEO Service Consultant - SEO Expert Danny
H1 Titles - main titles of the pages (About, Service, Contact
Images missing titles and name (ALT Tags) - Google can't read images, in code we use ALT tags, which tells search engines what images did we add to the site
Sitemap missing
Robots.txt forbidding Search engine crawlers to index your site
Lack of content on the site
Slow site speed load time. Website should load in less then 3 seconds by Google research, if sites takes longer than three seconds, bounce rate will increase for 40%
Lack of sites linking to us