Something similar to ID effect that I achieved without the I.D....

Take the card out from the box, ask the spectator to imagine a card...
1) Spectator visualize and say the card's name out loud

2) Magician will try to find the mentioned card without looking at the faces of the cards...

3) with only One try, The findings proved to be wrong, then of course pretend to say something like "I am still not that good..need more practice" or any line to create an impression that the trick has gone wrong or not done properly.

4) Then the magician, put the deck back into the box, ask the spectator to hold the box with the deck inside it, and visualize the number and the shape and say it out loud again and hope this time the magic works.

5) Take the cards out of the box "again", ask the spectator to spread through the cards and find a reversed card which is to be the spectator's chosen card.

Well, I never put any "mistakes" by purpose to achieve an effect but for this effect I had to because I need to manipulate the card. I need some advices and tips for this type of effect especially the "mistake" part because I am afraid of the espectator to be less interested in the magic.

The good thing about this effect and method is, it does not require an ID to achieve similar effect. The deck can be gone through and examined by the spectator.

Nice way. It really depends how the routine was carried out, cause the original ID deck is more direct. Since ur impromtu version need to have the mistake element, i will suggest that you dun do this effect straight first, do 1 or 2 strong effects, telling them that u are the magician, then proceed to telling them you have been trying something different recently, and will like them to see. Simply they will be interested because of the strong impact you gave them. Now do the wonder but if i am you, i wont put the deck back into the cover, but i will put the deck upfront in them, ask them to hold on the deck and name their card again, this time, telling them that the deck finds the card itself, revealing it loh.

Y i will say dun put back, unless you do a raise card effect from the cover, or else it wont make sense to put the deck back into the cover and take it out again.