Here are some ways it could be used:
* A colony of puffins: This is the most common and natural way to refer to a group of puffins.
* A flock of puffins: This is less common, but still grammatically correct.
* A rookery of puffins: This is more specific, referring to a breeding colony of puffins.
It's important to note that while "puffin" can be used as a collective noun, it's often best to stick with the more traditional terms like "colony" or "flock" to avoid sounding unusual or forced.