My experience and working system is bellow:
1. On and Off page seo (05 years)
2. Working system is:-
(a) keyword research.I can research manually using some [login to view URL] as google keyword planner,Keyword reveler, spayfu,kw finder,keywordsitter,semrush.I follow D/A,T/A,Backling.
(b) postion section.
URL character ratio,Title character ratio,Meta description character ratio,Meta keywords character ratio,Headings page implements HTML headings.,Images All images have ALT attribute.AMP plugin,Robots.txt setting,XML Sitemaps setting,Google Analytics setting and Favicon setting.
(c) Plugin task and configure.
(d) Page speed setting so that does not exist 3 second.
(e) keyword density setting, internal and external link ratio setting.
(f) Off page seo:-
* Guest posting
* Blog commenting
* Forum posting
* Social media linking and others.