To really work well, suggestions must be reinforced by repetition. Most of the habits, feelings and emotions we want to change are deeply implanted in our subconscious mind and will not just "go away" with one set of suggestions. Most of the time, the hypnotic suggestions need to be repeated on a regular basis until you notice a change. This is one reason that most specialists in hypnosis give clients cassette tapes of their sessions so they can listen to them every day. It's also the reason why hypnosis tapes you buy can work so well. You get to listen to them every day or often enough that the suggestions become permanently a part of you. There is no way to predict how long it will take to see change. It will depend partly on your motivation and commitment.
The Three Keys to the successful use of hypnosis for self improvement and personal growth are self motivation, repetition and believable suggestions.
The motivation to change must come from within you. If you are trying to change because someone else wants you to "lose weight" or "stop smoking", the chances are greately reduced that the hypnosis will work. For example, I've worked with many people for weight loss or to quit smoking who came to me because their physician or spouse wanted them to change. These people do not respond as well to the hypnosis as those who really want to change. Those who came because they wanted to quit smoking or lose weight responded quickly and easily. Before you start to use hypnosis for your self improvement, you should get it clear in your own mind why you want to change. This clear intention to change will help the hypnotic suggestions to take hold and manifest themselves in your everyday life.
The third key to the successful use of hypnosis for personal change is believable suggestions. If you are to accept a suggestion, your mind must first accept it as a real possibility. Telling a chocoholic that chocolate will be disgusting to them and will make them sick is too big a stretch for the imagination. If a suggestion like this even took hold, it would only last a short time because it would be so unbelievable to a real chocolate lover. In cases like this, one of the successful weight loss suggestions I use is that the next time the individual eats chocolate, it will not taste quite as good as the time before. This is far more acceptable and believable to most people. Then, with enough repetition over a period of time, chocolate loses much of it's positive taste and control over that person.
One final note: "Hypnosis is not dangerous." There are almost no risks when used by trained professionals. You cannot be made to do anything that is against your moral values. An amateur or stage hypnotist might give you suggestions that might embarrass you, might not work or that might make you feel uncomfortable or self-conscious at the time. To avoid this, stick with professionally trained hypnosis specialists. The one risk I know about involves falling asleep. If you are tired or if you become too relaxed, you may move from the state of hypnosis to the normal sleep state. This is fine if you were going to go to sleep right after the trance but if you have other plans after listening to a hypnosis CD, you may want to set an alarm clock just in case you fall asleep. I've even had students fall asleep because they became too relaxed. In relation to this, never listen to a hypnosis CD while driving. It is very dangerous for you and everyone else on the road. Don't even listen to it if you are a passanger as the relaxation suggestions could make the driver fall asleep.
Over the years, self improvement and personal growth using hypnosis has helped millions of people change their lives permanently because it is a safe and powerful tool for changing your thoughts, feelings and habits.