One of the cheapest and the google authorized linking techniques is to put a comment in any post of other blog or site.
Commenting is not something that you start doing everywhere you wish, if you are intended to get some SEO benefit to your site. Rather, you must have to be selective as per your site contents. Suppose, if you are running or managing a mobile marketing site, so it would be more better to comment on sites with marketing & sales in mobiles or at least should be dealing in communication products.
There isn’t any harm to comment the non-related websites but for SEO profit, you need to comment on related one. Two ways to comment, one is simply leave a comment and the site itself requires you URL email & name. In this scenario you can leave your keyword or site name in the place of name and the website URL you wanted to promote. Second method is to put a hyper link in the comment body as well if the site is accepting html tags.
When putting your name and url to make an in-link or the link back, if you are using site name or your highly valued keywords then, remember not to use your site name or the certain keyword exactly rather you can use a similar or elaborating one instead. For example, your site title is “Leather Jackets” so instead of using word Leather jackets, you can use “Winter Clothes” or “Leather garments”. You can use the original title at few places but if you’ll use it all the time, google will bypass either considering spam or the memorized old keyword.
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