Decide on a type of destination. Do you want warm weather or do you want to cruise by icebergs? Is there a particular country or city that you absolutely must visit? This will help you narrow down the cruise lines and ships that you have to choose from.
Figure out how far you are willing to travel for a starting point and how much you can afford to spend per person.
Look at the details for the cruises that fit your ideal. If you want to get dressed up, look for cruises that have formal dinners. If you prefer a more casual trip, look for cruises that offer night clubs.
Be sure that cruises you look at have important facilities. Things like movie theaters, spas and childcare facilities are not universally available. If a cruise does not have something that you feel you need, you can easily cross it off your list.
Look for signs that your cruise will have the atmosphere you want. The best way to figure out the general atmosphere of a cruise may actually be through their advertising. Look at images of cruises on the line's website. Are people partying hard, or dressed up? Are they relaxing in a spa? Swimming in a pool? Use this to help you gauge the theme of a cruise line.
Call a travel agent to help you book your cruise. Let the agent know what you have concluded and ask for his input before actually booking.