Once it's cooled down some, I switch to using my hands ... expecially as it helps to find any bones, globs of fat, etc.
I find it goes much faster, particularly if you're dealing with anything other than boneless breast meat. ...
but it shreds easiest while it's still warm, so if I'm doing a fair bit, I'll break a bit apart using forks, let that cool, break some more apart with a fork, then shread the first bit before it cools too much, repeat.
(so basically, I have one set broken down somewhat to cool faster while I'm shreding an already-cooled off bit).
update as justkt mentioned, the cooking method matters --
roasting and other high heat methods are going to cook the outside faster than the inside.
I typically poach my chicken if I'm going to be shreding it -- bring water to a boil, add chicken, bring back to a boil, turn to low, then leave for an hour or two ...
the low temp gets it all nice and tender, while the boiling kills surface bacteria.
cooking.stackexchange.com/users/67/Joe
Boiling the chicken is the easiest cooking method to prep for shredding.
Searing and baking make it a lot more difficult.
I too go with a combination of the two forks and hands (depending on what seems easier at the moment) method.
cooking.stackexchange.com/users/1816/justkt
One method is to use a stand mixer.
Put the meat in with the paddle attachment and pulse for a few seconds at a time until shredded.
cooking.stackexchange.com/users/8446/Bri
I just use my hand mixer while it's still hot takes me about 30 seconds!
cooking.stackexchange.com/users/12872/Kristi
I recently picked up a pair of Bear Paw Meat Handlers and they actually work quite well for this if you can't wait for the meat to cool down.
Hope
this helps someone!
Update:
I ended up purchasing some insulated latex cooking gloves which allows me to use my hands even when it's right out of the oven.
This is the best method I have found by far!
cooking.stackexchange.com/users/1000/Brh
If I'm shredding it for soup (mmm, tortilla soup), I just use a stick blender.
cooking.stackexchange.com/users/3819/Dave Griffith
Usually I will just cook it and then tear it to pieces using two forks, but this is still pretty time consuming.  Are there any secret ways to easily do this?
What is the easiest way to shred chicken?
cooking.stackexchange.com
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cooking.stackexchange.com/questions/7260
cooking.stackexchange.com/users/1000/Brh
Boiling the chicken is the easiest way to prepare it for shredding, then you can break it apart while it's still warm. A hand or stand mixer will save some time, or you can use a stick blender if you're shredding chicken for soup. Boil the chicken and shred it with your hands while it's still warm. You can also use a mixer.
Boiling the chicken is the easiest cooking method to prep for shredding.
Shred it with your hands while its still warm. Boiling the chicken is better for shredding. Try a stand or hand mixer to shred the chicken.