The following are not tricks but more or less some basic ideas of mine.
When talking about increasing traffic one has to focus on his target audience. That is like the first question that he has to find the answer to. What do readers of particular topics or consumers of particular services look for?
He could make his service, that offers whatever that is it offers, be the best one in the world according to his view. This doesn't mean, though, that he or his site will become successful or popular. Why? Cause his best ain't my best, your best or the customers' best.
My suggestion to anyone is to start analyzing his target audience very carefully before implementing any sorts of techniques. He has to try and find what keywords regular people use when they are searching for such services/products/topics on the Internet. He has to add quality content to his site (relevant with the original site content, of course) that will be built around these key phrases. And let's not forget that it is not just keywords here, that he has to focus on, it is the business model that he has to rearrange according to the needs his customers have.
It would also be a good thing if he focuses on being a "superstar" rather than being the average mediocre product or site. If everybody in this business go left he has to go right in order to get the desired attention and become remarkable in the eyes of people.
If he becomes that "superstar" in the eyes of the consumers of the particular product or service then he will more likely get noticed by others as well.
That's all from me on this topic. Hope to hear other inspiring ideas and thoughts.