Hi,
I use a light box that I built out of foam core board. I also use a single halogen desk lamp for my jewelry photography. You can find instructions on how to build my light box on my website- http://www.inexpensivejewelryphotography.com/photolightbox.html
I also recommend that people use a tripod and the camera's self-timer.
One of the reasons why people can't take good photographs of their jewelry is because they didn't read the camera's owner's manual first. By not reading the cameraa's owner's manual you won't be familiar with all of the camera settings which will result in poor photographs.
Another mistake that many people make when photographing jewelry is they fail to fill up the entire LCD viewing screen with the jewelry they are photographing. This makes it very hard for people that see your photograph onine to see all of the fine details of the jewelry item that you made.
Indirect sunlight is the best type of lighting to use for photography. An overcast day is great for taking photographs outdoors.