Learn to sail!
Learning to sail is one of the most enjoyable and fulfilling experiences you will ever have the pleasure of, and there are many ways of going about it. While people may try and sway you either way, it is important that you learn in a way and at a pace that feels comfortable to you. Below are a guideline of the various ways of learning to sail, and steps you should take, as well as one or two handy guides for the beginning sailor.
Crewing

Crewing on a friend's yacht or dinghy is an effective and virtually cost-free method of learning how to sail, if you have a friend with a boat that is! You will be able to develop your skills in a comfortable and fun environment, and (depending on how nice your friend is) most likely all for free! On the other hand, you are not receiving the benefit of competent instructors with years of qualified experience behind them, and so you may inadvertently be taught incorrect practises or boating etiquette.
Sailing Club
If you don't have a friend with a boat to learn on, then a sailing club is another good place to begin. While many clubs focus on racing, their members are often more than happy to take time out of their schedule to give you a bit of tuition, usually with a relaxed atmosphere, and at no cost, though this is all at the discretion of the club involved. This is a good way to learn, allowing you the benefit of meeting and making friends with other like-minded individuals, usually with many years of advanced sailing experience behind them.
Teach Yourself!
Uh-oh...!
In the UK, you don't need any qualifications to set sail, so it is possible to buy yourself a boat, take to the water, and teach yourself! You should ensure that your boat is fully insured against anything which may occur, particularly at this early stage of learning when collisions are most likely, and try and sail in a quiet area so you will not cause a hazard to other water-users should you lose control. That being said, sailing clubs are a good place to teach yourself, as they often have safety boat cover, should anything go wrong. This is a good route to take when learning to sail as you don't have to fit your schedule with someone elses, but it is advised you gain a little bit of tuition first, not only for your benefit, but for the safety of others also! Plus sailing can become very expensive when you buy a boat, and then realise that it isn't for you!
Courses

RYA approved sailing courses are one of the best ways to learn how to sail. You have the benefit of a qualified instructor, who will be able to answer all your queries, and teach you in a safe and controlled environment. Courses are often held over weekends, lasting 2 or 3 days with accommodation provided, and you should come out at the end with an internationally-recognised sailing qualification. The only downside is of course, the price, with 'Start Yachting' introductory courses beginning at around £200, it is an expensive way to learn, with prices increasing for the more advanced 'Competent Crew', 'Day Skipper' and other courses.
Sailing Holidays
Many people nowadays are combining learning to sail with a luxury holiday abroad, and prices are becoming more affordable. There are several types of sailing holidays including: Sailing schools, where you live aboard a particular yacht for the holiday duration, being taught by an instructor who stays on board with you; and Flotillas, for the more experienced, in which you take control of a boat, but sail around with several others, as well as the hire company's support boat, there to aid you should anything go wrong. Alternatively, there is the bareboat charter option in which you take full control of the boat with no instructors in site, though you will need sailing qualifications for this kind of holiday. Unfortunately, the expert tuition and luxury locations put a hefty price tag on sailing holidays, but they are a fantastic way to learn in a relaxed atmosphere.