Shop around, together as a couple. This way you avoid later disappointment and exchanges. Take into account the kind of work and lifestyle the person who is going to wear the ring has. Ask questions about diamonds, metals or anything else you think of – a good jeweller should be able to answer your questions.
It is estimated that you should spend at least a month’s salary on an engagement ring. In my opinion, you should spend more on the ring than on the wedding dress.