First of all, we should understand what is a niche market.
It is a group of people with common interest, a group who has the same hobbies, or the same social background, ethnicity. They will have the same desires and need. Each niche need informations and solution to their problems, and it is an extremely targeted market.
Your roleas an Internet marketer start here. How? You will give them what they want. Not something you are trying to sell to that niche by a forcing or a massive attack, but something they have to buy. Something you discovered that is vital for that niche. For example, you can' t come with the latest karate gi (kimono for the non martial artists), and present that gi with a massive advertising campain to a football team? You will spend tons of money, and you won' t make any sale. But if you understand the needs of that niche, what they are passionate about, what they are dreaming of...
Now you will come with products they simply can' t live without.
That' s powerful, you will have literally nothing to do to sell. Just present them the products, and that' it they come like the mouse follow that peace of cheese, they rush from everywhreto buy from you, they are complaining because your product is not available in their country, they advertise your products to their nichemates; the effect is viral.
It leads to residual income, because these people will buy from you other and other, they have no choice, no alternative, they can' t miss that.
Now I hope you understand why you have to target a specific niche with the specific product, the big deal.
So let' s resume:
Find a niche market, it' s easy on the web, you have all the tools that you need for free or small fee. Find out what they want. Present them a product that satisfies their needs.
Come to them with convenience: come with something they are searching for, for days or months, or they already found it, but you come with a new one, more sophisticated, who fit exactly their needs, the answer to their questions, take a old product who worked in the past in that niche and make a survey to find what you will add to this product or remove from it which will make the difference.
Or you can come with a very new concept that they maybe was not aware of.
Think about the cellular phone, people din' t know 10 years ago that it will be crucial to have a cellular phone. Who can leave without a cellular phone today?
Do your homework now, and find what people want.