I carry around laminated cards. Each has a different drawing: a baby, birds, tea, etc. I actually took the cards I bought once for "The Empress" effect, laminated them and now use them this way.
Everything is in the hands, showing the spectator each drawing.
Square up the 30 or so cards.
Take a small post-it, put it on the back card, and draw the one drawing you think the spectator just thought of.
Go through the cards again. Spec points out her thought-of drawing.
Turn the whole pack of cards around. On the back is your post-it-- the drawing on it is the same one she thought of.
Explanation: first saw the method on a DVD by British corporate magician whose name escapes me: a card prediction trick called "Storm Force" something. I just used post-it notes and bigger, laminated drawings.