It all begins with a clear understanding of the type of images you want to sell.
Are they nature photos? Do you have a huge collection of antique photos that you would like to somehow profit from? Maybe you have done a ton of fashion photography that would be an ideal selection for a start-up magazine or website? You must know the "type" in order to create the kind of interest that will be of benefit to you, but you must also understand that some markets have a lot more turnover and activity than others.
Consider that most of the stock and microstock companies see a lot of selling around business photography.
This means that performing a bit of research, looking at what is selling and what is stagnating, and crafting some of your work to meet the need is one of the first and wisest steps in attracting some attention.
Of course, you may not want to do the work just to make the sale.
"What about my art or my vision?" you might be saying, and that is understandable, but you will have to identify a niche and structure your work to fill that niche while also fulfilling your creative urges.
For example, if you are someone who regularly takes images that fall strictly under the category of "nature" you should head to a few stock and microstock sites and type in the word "nature".
You will be shocked, perhaps, to see that there are hundreds of thousands of images available.
So, how do you refine your work to stand out from the masses? You look for a missing specialization.
For example, where do you live? Is there a distinct lack of photographs of the special features of the natural landscape, or of the creatures that inhabit it? For instance, if you live in a desert area, have you noticed that there are not a lot of photographs of the flora and fauna that inhabit this region? You could take your love of nature photography and focus on specific images to fill such a niche.
Of course, one of the easiest approaches to selling your art is not even in the online world.
Instead, you might begin by visiting local cafes and restaurants to see if they have an interest in displaying your work.
Participating in fairs and festivals is a great way to get yourself noticed as well.
Once you begin receiving attention in the "offline" world, you should then develop your website and use microstock opportunities to get yourself even more attention.