I have 2 ways... The morning of feeding day I will move them to the fridge. They are thawed out by the evening time, then right before i feed them, I heat them up a bit with a blow dryer. Or, if I forget to take them out of the freezer, I will put them in a bowl of hot water. They are usually ready to go after about 45 minute (that's a small rat). May take longer for larger rodents.