Hlo Friends,
Can anyone tell me, What steps would you follow to optimize a website?

There are basically two techniques - on page and off page.

On page seo refers to the process that is followed on the website itself. Some of the tasks involved are:

Keyword research
Meta tags and title
Meta description
Robots.txt file
Sitemap generation
Content development
Image optimization

Off page refers to the link building and promotion of your website in search engines. Some of the most effective off page activities are:

Guest posting
Article submission
Press release submission
Social bookmarks
Classified ads
Infographics submission
Social media optimization

keyword
meta tag
title
back link
quality content post

Just add your web to "google insight" tool, then they will show you what you should do to optimize your site on both computer and phone