You can purchase high quality audio subliminals or you can also download some of them for free from the Internet. You can find these downloadable items in torrent sharing sites.
So before anything else, re-focus on your goals. Make sure you set reasonable goals. One way of doing this is to set a weekly goal that you can work hard on at the present moment. Some set long term goals and lose their drive along the way. But if you have weekly goals (and perhaps a reward waiting at the end of each week), you will be constantly driven and motivated.
Record your messages. This is the easy part. All you have to do audio subliminals is talk into the microphone. Just be sure to speak clearly and confidently. If you are going to talk to yourself you might as well talk in a manner that helps you build confidence.
Believe me, you aren't the only one thinking this. There are so many Internet sites claiming to sell subliminal CDs and MP3s that have just instantly appeared. However, some of these stand out as being instantly fake and unprofessional.
So you need to train your mind. You have to make your mind want to live the healthy life; you have to convince it to think negatively towards unhealthy food choices and keep an eye out for healthier food options. This way, you don't need to exert effort in fending off temptation. Once you see an ad for a fast food chain, your mind automatically registers that it's bad for you so you do not get taken in.
You can utilize these CDs or subliminal songs when you are meditating or visualizing. These are also times when you are very comfortable and your subconscious mind is very easy to tap.
There's no time limit on how long you should meditate. It can be in minutes or even hours. The most important thing is you get the outcomes you expect.