There are three very important stages in the Customer Purchase Lifecyle that you need to be aware of. These are typically the controlling factors deciding how close a prospective customer is to becoming a paying customer (your ultimate goal). The better your understand these phases, the better you will understand how to approach the customer at those particular stages.
(1) Research Phase
People love to learn before they buy, they're hungry for information on a particular topic, however they may not have product awareness yet. Although some purchasing decisions are more spontaneous than others, people learn about a concept before they consider buying something, and this "learning" is done using many mediums. These could include television, Facebook, Twitter, a Google search, a magazine, personal contact, from a celebrity, or a news website.
People naturally gravitate online to complete their research, as it is the "information highway". You can find information on virtually anything through a simple search in Google, thus why the majority of the research is done on the net and this is where you can locate a good deal of people when they are in their research phase.
The best approach at this stage: During this phase, the best approach is to get people onto a mailing list or get them following you via your social channels (Facebook, Twitter, Google +). From there you can work towards walking them through the remainder of the process, as you are not likely to make an instant sale at this point. If you engage people at this point via your content, you will likely be able to get them to revisit your site at a later date as well.
(2) Decision Phase
Some people have already made up their mind as to what product they are going to buy, and they want it now. For most people though, they will go through a decision phase where they research a number of products/services and decide which one best suits them.
Someone's decision can be easily persuaded by reviews and personalized opinions of others. This is where a great Internet marketer can intercept an individual, showcase certain products that are relevant and of high quality, and deliver a convincing review to encourage a decision.
People at this point are typically looking for product reviews or further product insight via their favorite online channels, whether this is reading blogs, doing research in Google, asking people on Facebook, or sending out a tweet.
The best approach at this stage: This is a very good phase to pick up potential "customers" . At this point, it is best to review products or services that the person is looking for. Sometimes people are looking for negative reviews and you can also leverage these as there are many "debunk" products out there, in almost any market. Typical keywords within this phase revolve around review, scam, comparison, information, and versus (comparing one product to another). People are very likely to buy at this stage if they feel comfortable with your review and you can build immediate trust.
(3) Purchasing/Action Phase.
The final phase is the one that is profitable to us as Internet marketers. No commissions will be paid unless there is an action that takes place! Whether this is a click, a lead, or a sale, a visitor needs to become a customer to fulfill the lifecycle.
During the purchasing phase, it is very difficult to detour someone from their purchasing decision. They have done their research, made the decision, and now are fully prepared to buy. In an ideal world, you would be able to target all the people within this phase, but often times the research and searching is complete at this point. An example of a search term that would target people within this phase would be "purchase product_name, order product_name, buy product_name, best price on product_name".
The best approach at this stage: The ultimate goal is to get someone to this point, whether you are able to do so through manually walking them through the process, or you catch people in the decision phase and help them buy. If you are targeting the keywords as mentioned about (the buy type keywords), you simple want to point people in the direction of the product they are looking to buy (through your affiliate link of course) and you are sure to convert very high. This is the ultimate phase to catch someone in, but it is the most difficult to hunt these "ready to buy" crowd down.