Now, to start, I don't consider myself a big seller or a success just yet. I've got a ways to go, so take my advice with a grain of salt. However, I was really getting frustrated with my sales, especially since I didn't get really any holiday sales. Then suddenly, in the last week or so, I've had 8 sales. That's an average of one a day, when I was normally selling 1 every 2 weeks or so. Of course there are many factors to consider, like the fact that it's the holidays and people are spending. Maybe my sales will drop off suddenly after the holidays, who knows?
But I wanted to share what I think has helped. I started trying lots of new things. When one thing doesn't sell, I try something else. My detailed, intricate greeting cards aren't flying off the shelves, so I wanted to concentrate on something else. At one point I tried magnets, didn't work so well. I tried offering sets of cards, still nothing. My latest attempt is to make handmade embellishments for crafting. These are the types of things you'd buy in the store, but since I make them myself, you can't find them anywhere else.
This is not to say that making supplies is the solution for you, but make sure you are always brainstorming new ideas, always trying new things, even if they don't all work, and you will eventually find your groove! When your shop feels stagnant, and you've tried everything else, tweak your product!
I hope this helps, and I hope my sales continue. But if they don't, I'll just keep trying new things. Just because something sells well outside of etsy, doesn't mean it will on etsy. Experiment with what does sell well on etsy, even if it is different from what you normally do. But make sure you're still doing what you love!