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Zoltan, Everyone brought up some good points.  Yes, keyword research is what you need to strive for but I would definitely shoot for some diversity in your link building and anchor text. Also I would build inside out...for example yes you build t-shirts, but let's go for the longtail keyword first the "Jules Vern Custom t-shirt" or "20,000 leagues under the sea" t-shirt.  This will help you build for the longer tail keyword quicker than the short tail, but you also need to remember not to forget about those short tail keywords such as "graphic t-shirts", "book t-shirts" etc. Before you do anything though, I always ask my clients to answer the following questions: What are your business' goals? How do you plan to market your t-shirts through inbound marketing? How have people found you in the past? If you can answer the those 3 questions, it might prove to be beneficial in both your marketing and link building tactics.