Do some research, go to
http://www.craftcount.com and look at the top selling shops in the category that you're in. That's going to be as good as you can get selling those items.
See how those shops operate, how many items they have, what their pictures look like, do they have a blog, facebook etc.
The top selling category is supplies, there are a lot of buyers for supplies.
The top sellers in other categories have hundreds of listings each, and the pictures are high quality.
You have to have a large, high quality catalog in a category that sells well.
Best regards,
Gary