Assuming you are referring to the Zener deck of ESP symbols, there are so many effects out there I don't know where to start!
First of all, get yourself an ESP deck; I would recommend Beyond ESP 2 by Magicbox. Bicycle also have their own version, as does Piatnik. Royal Magic ESP cards are quite nice and inexpensive.
As for ESP effects, one of my personal favourites is Zennerism by David Britland. There are also several on the Submodalities DVD, which is well worth getting. There is a booklet called Magic with an ESP Deck by Sam Dalal, which is excellent. Looch describes his highly regarded ESP effect in his book, Simple and Direct Mentalism; the same effect also appears in his DVD, Your Thoughts are Mine! Doug Dyment also has a couple of books which include his fine work on ESP effects and stacks. There are also a few ESP effects in Mind, Myth and Magick by T. A. Waters.
I'm just brainstorming there, and no doubt there are many more sources for ESP effects. But those are the ones that spring to mind right now. Most of the material I've mentioned above has been reviewed, either here at TM, Magic Bunny or The Magic Cafe (not to mention other forums and websites). Do a little digging around and research; there is a world of ESP material out there, with plenty of reviews to be read.
To answer your question and get you started with the minimum of fuss, try David Britland's excellent Zennerism effect...
http://cardopolis.blogspot.com/search?q=zennerism