You will have noticed some big changes in web design in recent years. Typically a modern website has a lot of white space around all page elements; logos, banners, text and break out boxes all have a lot of space around them.
The reason for this is the main means of navigation on a mobile is your index finger, and compared to a computer mouse pointer, it is a blunt tool and therefore plenty of space is required around navigational elements.
You will also notice that the main site navigation itself is put in a little box normally in the top right on a mobile phone. This is called “the hamburger” and is used to collapse navigation. If you tap it, it creates a fly out panel that shows you a tree structure for the menu.
Making a mobile-friendly website meant that it would load in one column and the navigational elements still be accessible.
Google developed its mobile-friendly tool to allow people to test their site against Google’s rules. If it passed Google would preference your site on its mobile search results page.
The next step, however, is “responsive design”, which includes the above mobile friendly requirements. Responsive design resizes the website to whatever device it is being displayed on whether that is one column on a mobile phone to columns on a tablet or four columns on a laptop and a desktop. All this is done with style sheets and there’s no return to the server to get more files which load slow load times.
So in terms of design, the gold standard is a mobile-friendly and responsive website running under SSL (encryption).
Ticking all those boxes will get you to first base with Google. Having a good breadth of content and regular changes to your site will get you to base two. Having quality backlinks, YouTube content and regular social media posts will get you to base three.
Hitting a home run however, that is, getting on the first page of the unpaid, organic search results is very difficult and can take a long time, hence the Google Adwords program.