To get the most out of any holiday, the first rule is to make sure it is the right one for you. When it comes to cruises, there is a bewildering choice of lines, ships and voyages on offer to the 1.8 million or so Britons expected to take a cruise next year.
The most thorough reference book for potential passengers is the annual Berlitz Guide to Cruising & Cruise Ships, which reviews nearly every ocean-going ship in the world. The 28th edition is out on 1 October, and its first ebook version launches this weekend, coinciding with the start of National Cruise Week. Its author, Douglas Ward, has sailed across the Atlantic 157 times, and spends about 200 days a year at sea. His mission: to examine every ship right down to the last detail. Here are Ward's top five tips for booking your dream cruise.
w Be wary of internet agents' prices. As with no-frills airlines' websites, all sorts of non-optional extras, such as port taxes, can appear at checkout.
w Book through a specialist cruise agent, in person or on the phone. They'll know the ships, and be able to answer any questions, as well as give perks such as on-board credit and cabin upgrades. There are plenty of excellent agents. For example, staff at both Mundy Cruising (020-7399 7670; mundycruising.co.uk), for luxury lines; and Bath Travel (01202 200740; bathtravel.co.uk), for big-ship cruising, can help you to choose your ship and cabin.
* Book early. The best cabins go quickly, and the longer you leave it, the less choice you have. If you are tied to certain times of the year, like school holidays, there could be no family cabins left. Get a price guarantee from lines such as Saga and (for departures from next April) P&O and Cunard, which offer on-board credit or cabin upgrades to the value of discounts introduced after booking.
* On the same budget, you'll have a better experience in the cheapest cabin on a five-star ship than in the owner's suite on a lower-grade one. Big resort ships spend about £8 per passenger per day on food, but upscale companies such as Silversea and Crystal splash out up to £20 pppd.
* The best ships for families are: Independence of the Seas (royalcaribbean.co.uk), with lots to keep teenagers occupied; Azura and Ventura (0843 374 0111; pocruises.co.uk), which have good nurseries; and MSC Opera (0844 561 1955; msccruises.co.uk), sailing from Southampton next summer. Under-18s sharing their parents' cabin go free (but must pay port charges of £105 each).
Berlitz Complete Guide to Cruising & Cruise Ships 2013 by Douglas Ward (£17.99); insightguides.com/berlitz