You can use your pendulum to cleanse your tarot deck.  
 What you will need:
~  tarot deck you wish to cleanse
~  your pendulum
First, fan out your tarot deck on a clean surface facing up.  Now swing your pendulum side to side across the entire tarot deck.  Envision your pendulum clearing the negative energy and replacing it with golden positive energy. 

That’s it, your done!  Be sure to cleanse* your pendulum after you are finished.  
pendulum { CrowningElements }
tarot deck { Shadowscapes Tarot }
{ this gorgeous deck features the art of Stephanie Pui-Mun Law she also has an etsy shop }
tarot bag { EarthRitesBags }

*It is important to keep your pendulum free from negative energy, so smudge it with sage or incense, or leave it out under the moon to clear at regular intervals.
Now you go try it!