I don't believe it is possible to hypnotize a person. They have to be willing to play along and pretend with you, but at some level I think anyone you see being hypnotized, like on a tv show or something, knows they are still in control of everything and just going along with things.
I may be wrong, but it is just my opinion. I was once at a show with many people being hypnotized on stage. Some of the people that did not "go under" were told to go back to their seats, which was most of the people. I sat next to one of them and they said they felt pressured to go along and do whatever the hypnotist said so they would not look like it did not work for them. Some could not do it well enough to make it look look real and were asked to leave. I think the others on stage were just very good at acting, so they stayed.
The closest I ever got to maybe feeling hypnotized, but only for a few seconds really was the following.
Chinese Handclasp
The following is a variation of the hand clasping experiment. Have your subject extend his hands and arms in front of him, palms facing one another. Now tell him to bend his hands so the palms face him and the tips of the fingers are opposite each other (Fig. 3A). Next have him spread his fingers apart and bring his hands together so the fingers interlock and touch at the base (palms still apart). See Figure 3B. Now tell him to rotate his hands so he sees the backs of his hands (Fig.3C). Finally, have him elevate his hands above his head, palms outward and his arms outstretched as much as possible (Fig. 3D). Demonstrate the procedure as you as you tell him what to do. Then have him go through the procedure, step by step. Then say to him:
Please look into my eyes and listen carefully to what I tell you. Keep your hands above your head, arms extended and fingers interlocked. Think of your arms stiffening and your fingers becoming tight. As I speak your fingers and hands are becoming tight. Your arms are becoming stiff... Think of nothing else... The muscles of your arms and hands are becoming more and more tight, stiff. Your hands are getting tighter and tighter, your arms are becoming stiffer and stiffer. I am going to count from one down to three; at the count of three you will not be able to unlock your hands and fingers. One...Your hands are getting tight, very tight, so tight you cannot separate them. Two...Your hands and arms are getting stiff, stiffer, so stiff you can't move them. THREE...your hands are stuck. Your fingers are locked together. YOU CANNOT TAKE YOUR HANDS APART, the more you try the tighter they become stuck. Try...You CANNOT...The more you try the tighter they stick together.
Some hypnotists prefer to give the above suggestions with the subjects eyes closed. Both methods seem equally effective. The important thing in this experiment is that nothing distracts the subject's attention from the suggestions.
Source: http://www.hypnosiseducationcenter.com/mod8-waking-d.html