There is no right or wrong way to choose eau de toilette for men, since fragrance is really a matter of opinion. You should consider the price range of items to choose from as well as any skin reactions you've had in the past. Whether or not those issues will be of importance to you will primarily depend on your budget and whether or not you have sensitive skin.
The primary factor most people consider when choosing eau de toilette for men is the fragrance. Most have musky, masculine types of scent that men usually wear. Others may be a little softer, or richer. There is a wide range of option to choose from, so it might take some time to find just the right scent for you. The only way to determine which ones will work best is to try them out.
Many companies offer free samples to allow customers to try fragrances before purchasing. Make sure you put the sample on your skin, since scents can often smell different from the bottle than they will when they're actually on. This will also allow you to find out if you have any skin reactions to any particular product before you cover yourself with it. In addition, you will be able to tell how long the fragrance lasts, since some products may not be worth the cost if they disappear within an hour or less.
Another factor you should consider when choosing eau de toilette for men is whether or not you have a history of skin reactions. Those with sensitive skin should choose products that won't cause pain, redness, or other irritation. Unfortunately, there isn't a way to tell which products will cause an issue and which ones won't until you try them. If you are prone to reactions or skin sensitivity, place a small amount of the product you're using on one area of skin. Wait several minutes, or even hours, to see if any irritation occurs.
Price is another main concern when choosing eau de toilette for men for many people. There is a large price range when it comes to fragrances, so no matter what your budget is, there will probably be something for you. Choices will be limited if you are on a very tight budget, but there are still many department stores that carry nice products for very little money. Just come up with a price you would like to spend before shopping, and then keep it in mind before making a purchase.