A few pointers when thinking about keyword marketing
Always have keywords in the page title specific for each page. Also try to have keywords in the page content as much as possible in a human friendly manner.
Try not to over repeat keywords in the title, meta tags or content of the site as this could result your site been band from search engines.
When thinking of keywords to use in your web page think broader then narrow, What I mean is if you searched for web design in Google there are 382,000,000 results to come up on the first page of Google with that many results is going to be very difficult indeed.
Lets try to narrow the results down if I search for "web design uk" in Google there are 17,500,000 results this is still very high so lets reduce the results further by searching for "web design hull" there are now 416,000 results with these results there is more chance of getting on the first page then there were with 382,000,000 results.
So when thinking of keywords try to remember start broad then narrow them down which will increase the odds of your web site been seen.