If you are going out to look for an engagement ring I always suggest that you do some homework.
1-Decide in advance what you are comfortable spending (You may spend more or less than your actual decision based on your final selection but KNOW THE RANGE THAT YOU ARE COMFORTABLE IN.
2- Look around & see what shape (THE CUT) of diamond that you like. Round diamonds are the most popular. Princess cuts second.
3- Study the various METALS. See what appeals to you & learn the different price points of these metals.
4- Look at different STYLES- a plain solitaire versus a solitaire with diamonds.
5- Start shopping. Go to different stores. Look on the internet. Get some ideas of the different costs. Remember the diamond cost represents the major part of your purchase.
6- Diamond costs will be based on COLOR(D,E,F,G.H,I,J) any of these colors are acceptable, CLARITY(VS,SI,I) , CUT(round, princess, radiant, oval, marquise) and of course SIZE (½ carat,1 carat, 1.50 carat, 2carat, etc)
7-Once you have narrowed down your choice in metal, diamond type& size, style of ring and the amount that you feel comfortable spending YOU ARE READY!
8- Pick the place where you want to shop, a small store, a large store, a chain store, the internet.
9- Communicate everything you know to the salesperson and try to get the best ring that you can for your money.