How do you get to be a puller that can pull animals from shelters?

Typically a person or group that is able to "pull" animals from shelters are rescue groups with their non-profit status. An animal is considered "pulled" when a city shelter has deemed it unfit for adoption for one or more reasons such as: age, aggression, illness, overcrowding, etc, but the shelter makes this animal available to recognized rescuers.

Most city shelters require a rescue person or group to have a good reputation in the rescue community and a 501 (c)(3) non-profit status, but sometimes smaller cities will allow animals to be pulled by rescuers with a good rescue reputation that does not have a 501.