Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve deception. One black hat technique uses text that is hidden, either as text colored similar to the background, in an invisible div, or positioned off screen. Another method gives a different page depending on whether the page is being requested by a human visitor or a search engine, a technique known as cloaking. Another category sometimes used is grey hat SEO. This is in between black hat and white hat approaches, where the methods employed avoid the site being penalized, but do not act in producing the best content for users. Grey hat SEO is entirely focused on improving search engine rankings.
For the most part, the 6-figure, 7-figure, and 8-figure-earners and up are making a large majority of their income by scaling out offers that they control. If you're just starting out, that avenue isn't for you. It only comes over time as you come to understand the field. As Sharpe says, most people first need to get a lay of the land and cruise through the virtual sales landscape before they dive into a massive undertaking like creating their own digital products and sales funnels.
Many blogging software packages automatically nofollow user comments, but those that don't can most likely be manually edited to do this. This advice also goes for other areas of your site that may involve user-generated content, such as guest books, forums, shout-boards, referrer listings, etc. If you're willing to vouch for links added by third parties (for example, if a commenter is trusted on your site), then there's no need to use nofollow on links; however, linking to sites that Google considers spammy can affect the reputation of your own site. The Webmaster Help Center has more tips on avoiding comment spam39, for example by using CAPTCHAs and turning on comment moderation.
One common scam is the creation of "shadow" domains that funnel users to a site by using deceptive redirects. These shadow domains often will be owned by the SEO who claims to be working on a client's behalf. However, if the relationship sours, the SEO may point the domain to a different site, or even to a competitor's domain. If that happens, the client has paid to develop a competing site owned entirely by the SEO.
In addition to measuring your website traffic, you need to track your conversion rates. For example, if, as a result of your search engine marketing efforts, your traffic doubles from 250 to 500 visitors per month, how many new customers did you acquire from the additional 250 visitors to your site? Do you now have twice as many customers as you did before? If you picked up 5 customers your conversion rate would be 2 percent of the new traffic (5 divided by 250) and 1 percent (5 of 500) overall.