I'm guessing you mean "tuo"-shaped pu'er; often referred to as bird nest shaped. You need to get a good pu'er knife, Mike often says he uses an oyster knife that works just as good, to break apart a small portion of the tea to prepare it for brewing.
I've heard many people say many different things about how to break the tea off. Some poeple turn the tuo upside down and push the knife into the hole in the middle and get the tea that way. Some people try to insert the tip of their pu'er knives into the side of the brick and move in a circular direction to get the tea that way. Still some people prefer to take from the ridge of the mouth of the tuo (circular motion) inside or outside. I prefer the latter; taken from the outside.
Whatever you do, be careful. If the tuo is too strong, you can injure yourself with the knife...and how would you explain that injury to your friends? I did it drinking tea?
heh.