It all depends on you 'guessing' the search string someone will use as a starting point.
I have spent ages working on my sites rankings with google.
If you search for 'gas boiler installer in norwich' I usually come up 1 on page 1. If you search for gas heating installer in norwich, then I drop to 3.
Google tend to change their algorythms approx every 3 months to try to keep the SEO's on their toes and to get more genuine results.
Google did release the fact that they work on 'relevant' links to your site as opposed to any old site have a link to you, such as a general link exchange site.
The keywords in your page title count for a lot, but also keywords in the descriptive body of text. It can also help putting keywords into the code for any pictures on that page. Having a sitemap.xml created and entered into your page code will also help. Bots like reading these. There are many free sitemap creators on the web. You don't have to understand them, I don't
as they are automatic.
If the bots find that you are trying to fool them, such as filling the page with keywords in the same colour as the background, you will get penalised or even removed from the rankings.
You also need to make sure that you have the code on your home page (index.html usually) to tell the bot to look at all your pages.
It can be a long and time consuming process and take up to 8 weeks for results to appear and just when the results happen google moves the goal posts again
Good luck