To determine your labor costs, divide the time you spent working into 15 minute segments. It makes it easier to calculate price. If you spend a little over an hour making a certain piece, round it up to an hour and 15 minutes. You can charge more for custom made pieces. Keep in mind, this is only the cost of your time, this is not your actual salary. You charge whatever you believe your time is worth. Do not, however, charge ridiculously high labor costs if you're just starting out. If you already have a reputation, as jewelry maker or other, you can charge higher prices.
If, for example, you have priced your labor at $20 per hour and worked for 30 minutes on the design, you would multiple 20 X .5 = $10 or divide in half. When deciding how much to pay yourself hourly, consider your experience. How long have you been designing jewelry? If you have a long track record, vast expertise, and a portfolio of unique designs, you may find that you can charge more. You may also have particular advantages, including contacts and unique designs, that allow you to charge more.