If you are planning to propose to your partner, then you likely know that women today still expect men to have diamond engagement rings in hand when they propose. However, there are so many types of diamond rings that you may be overwhelmed by all of your options. While many men simply let their future fiance's choose their own engagement rings, women do still love being surprised with rings their partners pick out all on their own. 

To be able to surprise your fiance with a beautiful diamond engagement ring while still ensuring that she loves the ring you chose, follow these two steps to choosing the perfect ring for her. 

1. Choose the Diamond Cut Based on Her Personality & Personal Style

While a classic round cut diamond will never go out of style, there are so many diamond cuts today that it is worth looking into them all to make sure you choose one that your fiance loves. The wedding-oriented blog called TheKnot.com offers some great tips for choosing a diamond cut that suits a woman's personality and personal style perfectly. 

If you suspect that your fiance will love a diamond cut that sparkles the most, then the best options are the classic round diamond and the princess cut diamond. While the classic round diamond has the most facets, which are the small cuts that cause light to reflect from a diamond and give it a great sparkle, the princess cut has almost as many facets and is best for a women who has a very feminine style. A heart-shaped diamond is another great option for a woman who loves feeling feminine and romantic. 

If your fiance has an elegant style and loves drama, then a marquise cut is a better option for her, and a pear-shaped diamond is perfect for a woman who prides herself on her quirky personality and fashion sense. 

Tip: To make sure you choose the right diamond cut, yet still be able to surprise your fiance with her engagement ring, ask her questions about what she thinks of the diamond rings that any of her or your friends or family members wear. Her answers can give you an idea of her diamond tastes without spoiling the final surprise.

2. Glance in Her Jewelry Box Before Choosing Her Band Metal

Along with an increasing number of diamond cuts that make choosing an engagement ring a little more thought-intensive for men today, there are also many more options for band metals. While yellow-gold used to be the "gold standard" metal for engagement ring bands, white gold, platinum, and even rose gold bands are rising in popularity. 

While all can look great, many women choose to stick to a certain metal in most of their jewelry, because each metal tends to look more flattering on women with different skin tones. For example, while a woman with "warm" skin undertones may look best in classic yellow-toned gold and rose gold, a woman with "cool" skin undertones will look best in platinum or white gold. 

You don't have to learn what skin undertones your fiance has when you just check out her jewelry box to determine which precious metal she owns the most of and stick with it when designing her engagement ring. By doing this, you will not only ensure that the metal you choose will look great with her skin tone, but you can also make sure it complements the other jewelry she will wear with her engagement ring, such as earrings, necklaces, and bracelets, well. 

If you are planning to "pop the question" to your partner soon, then you can let her choose her own diamond engagement ring to make sure she gets a ring she loves. However, women still love to be surprised when their partner proposes, and when you follow these two steps, you can surprise your fiance while still making sure she gets an engagement ring she loves.