How should a cat be picked up by the scruff in a safe and gentle manner?

To pick up a cat by the scruff in a safe and gentle manner, place one hand under the cat's chest for support and use the other hand to gently grasp the loose skin on the back of the neck. Lift the cat slowly and carefully, making sure to support their weight and avoid causing any discomfort. It's important to only lift a cat by the scruff when necessary, such as when handling kittens or during medical procedures, as it can be uncomfortable for adult cats.