Not everyone can afford the high end jewelry, especially if it's for a trend that probably won't be in style longer than two months.
When you purchase costume jewelry, especially cheaper, or less expensive jewelry, you want it to look like a million bucks each time you wear it!
For fake gold, usually as you wear it, it starts to turn to a bronzey tone before it almost turns black or green. To keep this jewelry looking its best, you want to make sure you don't wear it in the shower, and to store it in air tight bags when you are not wearing it. This will slow down the turning process of your jewelry, getting the most you can out of it! (Same with Tiffany's, their silver always turns, if you keep it in air tight packaging while not wearing it, it will stay shiny much longer!)
I don't know about you, but for me, cheap earrings don't mix well with my pierced ears. They either hurt after a while, or can cause an infection after extended wear. I always apply Neosporin on the posts or hooks of the cheap earrings before inserting them in my pierced ears. This always helps with the pain - I don't have any - and I try not to wear cheap earrings numerous days in a row, but if I have to, Neosporin definitely helps not to cause an infection.