Learn the basics of SEO
Backlinks and Other Links
Get listed on some directories. Check address listings for consistency. MOZ Local is helpful - https://moz.com/local/search
Website Indexing
Get your site indexed on Google Search Console. You can sign in with your gmail account.
Content or Blogging
The more content your site has, the higher it will rank. The more pages the better, but you want a decent amount of content on each (ideally 1800 words, but over 500 is ok). Add specific pages for each service you offer and a page with local info for each town/city you want to rank in.
Competitor Research
See which companies are ranking for the keywords that you want to rank for, click on their websites and get some ideas.
A great website gives a great first impression but doesn't do any good if no one can find it. With any website, you won't get to the top right away. It actually takes a lot of work! You can do SEO yourself, it just takes a while to learn it.
Want to learn more? Here's a guide to the Top SEO Ranking Factors of 2020.