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It will naturally strengthen for its exact match term with the adding of well planned and keyword rich pages, It will also get you traffic for any longer phrase containing that term if you do this. This is a much more efficient way to spend your time. You also won’t go as insane by wasting braincells and feeling ashamed for spending time trying to get worthless links for the sake of seo.
Aside from that, to get quality one-way links to the domain, you need to have money or be able to offer some sort of service to a another relevant webmaster in exchange for good linkage.
For quality link trades you’re going to want to actually build up a site that has good keywords in the domain (like bestslotsbonus.co.uk) and then smarter individuals will be exstatic to trade with you in good spots even if the site isn’t very old or showing strong page rank etc.