Now if you search for SEO and looks for tips and tricks from Google directly you will find some advise.
For example that google will start ranking pages that have and SSL certificate higher. Starting now.
Their next advise is to make a user friendly page that has lot of information the customer needs, info graphics etc. Now I have loomed at many screen print shop pages in the States over the years and I have to say most of them lack info. Most people have no clue what is involved in the process of printing a shirt. All this should be explained on the site. I would break down the whole order process etc. Make sure you have a site index too. And the page has to load fast.
Forget about back linking.
The only reason why we get an SEO guy is to go over on site SEO, such s meta tags, keywords and page titles.
All the rest is poo poo. Oh and do sone social media stuff on a regular bases.
We are redoing our page right now, all responsive design, adjusts itself to desktop screen size, mobile devices etc. No need for a separate mobile side in that case. My friend is a great web designer, I`m more then happy to forward his details to anyone here.