I would only add to the above answer that you need to build up your label reputation first. You may be able to break in to a consignment shop where you could keep track of your top selling items. Or you could try a local boutique and ask for a few of your items to be sold in their shop to see how well they do. And don't discount local fairs, flea markets, booths at outdoor local concerts, and downtown street festivals. My small California town has lots of selling options in the form of county fairs, regular flea markets, and festivals such as the Butterfly festival, the Autumn Harvest Festival, the Asparagus Festival, and so on. Earth Day had hundreds of booths at a local fair - a great way to have your product be seen and you can sell direct. By selling direct at these fairs and flea markets you can see exactly what products sell and what products are passed by. Then when you are ready to break into a certain store your label has past proven success.
Getting up my own inventory to start selling this next year!