We have already seen some aspect for the publication of an article to make selling a product or service, perhaps a manual or electronic material, the truth is that there are an infinite number of options with great potential for success, so, continuing in the task of making an effective publication we delve into the offer. Perhaps we already have defined the sector where we are going to invest, in the middle of both search, we have encountered the option that offers greater profitability and a lower investment; also have sought our potential clientele, to do this we locate sites that enable buying and selling objectively through a system of classified ads, free ads, pay per click or social networking systems. But now comes the most important part to ensure success, bid, although there is a target group with millions of hits, selling a product offers 2 levels of competition, the first is the interest of the product and the second is competition existing in the market. When I speak of the interest of the product, I am referring to the ability to attract customers that are not considered in the first instance to our publication potential. Normally this type of clients are excasamente seen as potential for competition in the market, which allows to capture the interest towards the product, make large sales potential. Will an example: I have spent I sell clothes for ladies, in this activity plays important role the desire for elegance, nato desire of women highlight their beauty, as well how I have an important audience in sectors where clothing is marketed for Lady, and clothing in general, also can I create possibilities at sites of fashion, makeup, and even in sites for dating, by placing an ad in this type of portals, perhaps a person to buy make-up, can see a dress from the collection that I sell, and can automatically take into account as well that would be combining both products.