Decide how you are going to wear it. Will you wear it to work on a daily basis or at night clubs on weekly basis? This step is vital, because it will let choose from a variety of stones available in the market.
Consider the outfit you'll be wearing at any particular party with the diamond necklace. To see if it will work, take your jewellery to the clothing store and see how it looks with the outfit you are considering.
Search for necklaces that enhance your facial features. First of all, precious stones, and necklace should grab your attention. If it does not appeal to you, then it will be hard for you to feel good. You should observe if it suits your skin tone, the shape of your face, the length of your hair and last but not least, your personality.
Use a magnifying glass to make sure that there is no defect in the stone before making an expensive purchase. Start with the upper face of the diamond as it might to show you dome scratches and stains.