Photo courtesy of Surreal Muse
A great example of what this tip is all about (go see)!
Bring your best.
Why are you wasting time listing stuff that is not the best you can make? For those who are just starting out it is so important that you make your best impression. So you put some beads on elastic and you only want $2.00 for it, they really break up the look of your storefront and over-shadow the awesome peyote stitch earrings you have listed. Sure, maybe someone will buy your cheap stuff because it is cheap but if you want your Etsy shop to thrive you need to put your best work forward and give the crap to your nieces (no offense nieces).
Your storefront on Etsy says everything. It takes time to make, photograph and list stuff. If you are going to put your time and your .20c in, make it count. Don't sell what you don't love, and if you are not great at what you make, get better. Take classes, try new techniques, keep trying. If you want your etsy shop to seriously work for you, make sure your customers know you take it seriously.