Establish your budget
Before you set foot into a jewelry store, know what you want to spend. A common rule of thumb is two months' salary, but it really comes down to what you're comfortable with - and what she'll be happy with. And keep in mind that most men end up spending a little more than they originally intended.

Be informed
The more you know about rings, the better prepared you will be. You'll be faced with decisions about the shape of the diamond, the setting style, and the choice of metal. The diamond accounts for an overwhelming majority of the price of the ring, so you'll want to choose platinum which will keep it secure while enhancing its beauty. There are always trade-offs to be made between the size, brilliance, and number of diamonds. But you won't want to compromise when it comes to the pure, rare and eternal nature of the setting.