Remote viewing is a classic mentalism trick you can perform
Before the show, ask one of the spectators to draw a simple design or picture, seal it in an envelope and keep it with them.
Later during the show, you invite them to think about the picture and after a period of concentration you draw something on a notepad.
You ask the spectator to open their envelope and reveal the drawing they made. You spin your notepad around to reveal a matching drawing.
You need to make a remote viewing gimmick to achieve this effect.
The first item you require is a black clipboard made of cardboard with a plastic coating. If you are unable to find a clipboard of this colour, any colour clipboard can be used. You can find these in most stationers.
Using a sharp craft knife, carefully cut along the bottom of the clipboard to form an opening across the whole width.
Next take a piece of carbon paper and tape it to a sheet of A4 paper at the top. Slide this into the flap in the clipboard until it is completely inside. Now glue the flap shut and using a black marker pen, colour the cardboard to match the plastic on the clipboard.
The gimmick is ready for use.
When you ask the spectator to make a drawing, give them the pad with a couple of sheets of paper clipped in it and a fairly short pencil. A shorter pencil forces them to press harder on the paper, thus creating a clearer carbon impression on the hidden sheet inside.
In secret before you begin your show, peel back the plastic and carefully remove the paper inside. The spectator’s drawing will be clearly visible thanks to the carbon paper. Most people will draw something simple like a house, a car or a face - so it should not be too difficult to remember. However, it does not matter if you get it slightly wrong - in fact, it may even look more like real mind-reading.
Performance tips include remote viewing which is ideal as the second effect in your act. After wowing the audience with your first illusion, you explain how you got one of them to make a drawing beforehand and ask them to produce the envelope. Hold it up to your forehead for a while then announce “No - I am not getting it - let us try something else.” Place the envelope somewhere in full view and never touch it again. Move on to some other illusions. You can then reveal the drawing much later as your penultimate effect, even having another couple of failed attempts during the show as a running joke.
On the subsequent attempts, just stare at the envelope rather than holding it and again announce that you are still not getting it and move on. Alternative methods for carrying out this type of experiment include observing the tip of the pen or pencil as the spectator makes their drawing to learn what it is and even special electronic clipboards that transmit the drawing to the performer, who views it on a tiny TV screen.