May I suggest a different approach?
Take a look at your ability and how you present your performance.
In terms of ability, you may not be performing the sleights in the correct manner. For example, if your hand is curved too much when palming a card it is obvious there is something there. Even if you are performing the sleights technically correct, you may still be telegraphing that you are doing "something." For example, you may be going to the deck to palm the card at an odd time (rather than doing a top palm in the motion of squaring the deck). You could be rushing your actions or taking too long when doing the palm rather than doing it smoothly. You may also be looking at your hands when you do a move. If that is the case, you just need to learn the correct technique (may I suggest Roberto Giobbi's Card College series over Youtube videos).
For presentation, if you present magic as a challenge, your spectator's reaction is appropriate. Much magic is marketed to fool the audience, but people in the audience don't want to be fools. Also, many magicians present magic as "look what I can do" ("and you can't") which really makes the audience want to demonstrate that you are not that special by ruining your performance. I also think that having "say-do-see" patter gets the same result. If your presentation consists of saying what you are going to do, doing it and then telling the audience to see the result, you are giving them nothing to focus on but what you are doing... is it a surprise that they think about HOW you are doing it? The solution is to focus on entertaining the audience and making the presentation about more that what you are doing.