Search Engine Optimization all the way. Start locally, I have said this to a million people, if you live in Plymouth and you want to offer web design, a client has to be able to type in...
web design plymouth - Google Search
and you have to appear in the top 10 at least for a place like Plymouth because people don't want to search through loads of pages to find you. Doesn't matter if there's a few badly designed sites above you as long as your design stands out a mile.
Look at the sites that are top and see their coding, wording, use of meta tags, H1 H2 etc, title of pages and amount of keywords in the copy and you will see why they are placed there. You need plenty of text links saying
web design plymouth pointing to your site from reputable places not free link directories.
Have enough detailed pages, good relevant content, a site map, blog maybe remember the more frequently the site is updated the more google will visit which is important if you want to put an offer out and get it indexed pretty quick.
The company that came top on my search doesn't have alot of text on the home page but take a peek at their sitemap and it will show you why they're near the top...
Minim Site Map
PS. you have 187 links on this site that say...
philjohnsimaging.co.uk
Nobody is searching for that, that would be a good start to update.